I THOUGHT wed spend time together month talking about couple engine problems received letter few months back Charly Pate Nashville TN Along few nice words about column Nats Charly askd following question What determines fuel tank should placed fuel tank heights referred relationship needle valve ie Set cen ter fuel tank needle valve etc Often tanks location shown plans remember Al Rabe once made fixture allowed him raise lower needle valve hoping coure fine tune engine shimming tank fail ure Sure would like see some comments Youre absolutely right Charly years standard recommendation has line up centerline tank needle valve ever Al others have found doesnt always trick Thus shimming position either tank engine obtain equal engine speeds plane either upright inverted has become necessary nui sance Stunt fliers ception know Fox 35 mounted either upright inverted one-inch-high tank mounted same level will almost always run exactly same both ways seemed clue somewhere put thinking cap re tired personal pondering place Fox 35 hand ST 46 other After consuming substantial sheets paper am ple ration caffeine heres what came up know little two-cycle wonders produce prodigious horsepower might aware secondary function performed engines bottom end ie crankcase area below piston part engine functions very efficient displacement pump performs two tasks First bottom stroke BDC bot tom dead center piston compresses charge fuel air crankcase cylinder bypass/intake ports open charge forced combustion chamber next compression/power-stroke sequence Second top compression stroke TDC top dead center volume beneath piston has enlarged because area sealed increased volume reduces pressure air trapped therein intake port crankshaft opens negative pressure neg ative respect surrounding atmospheric pressure draws air rapidly through venturi past spray bar thereby drawing fuel tank crankcase along Th IS LATED NIDIIAS EIIFIN III SCM NP FIOURE IIIEIKAIRtUIIC 7N CPA.. WNRIC IETERRIRAIIE IF TIE CIffiER IF N1193 ETILTI flow incoming air pumping action al ternately increasing decreasing pressure within crankcase coupled appropriate opening closing exhaust intake ports draws fuel tank rate fuel delivered engine thus determined relationship fuel tank pump trick deter point pump will call Center Pumping Action CPA Continued page 168 Ted just show off graphics capability new toy. er. computer believes hes solved longstanding mystery Stunt technology know position fuel tank engine will run same speed model either upright inverted Hes generated convincing answer months column Figure IV shows intake exhaust ports atypical 2-cycle engine positioned cylinder liner now somebody takes engine apart reassembles cylinder sleeve backwards occurs kind troublesome things happen engine performance including tremendous loss power 62 Model Aviation Conoi Line Aerobatics Ted Fancher 158 Flying Cloud Isle Foster ClAy CA 94404 Gerald Schamp Albany OR built hybrid imltationlOrlental Stunter really beautiful redand-white model Power originally OS 4OFP inadequate planes weight Additional power now comes Tom Lay-tuned ST 60 Closeup Below R shows double horn/double davis arrangement used round adjustment rudder offset RENIH PRESSURE RD EliOt lEE CENTER P119 IEDIT ~1~ ATEC -AIJIIICATER PIN VILE AT MITE OEM CENTER FIGURE IINISIPIESSIREAT IIETE-CVCIIEIIOIE IIF~iI TC9CEMCENTER jAPJ iiiEF Pill IIEIINIT in2Wh AT TIC Ij ATES FliP fLUE ST TEl OEM CENTER Tom Lay T&L Specialties says custombuilt ST 60s produce much power broke arm just starting up Hell still sell you order direct PO Box 6052 Torrance CA 90504 RELATIVE LOCATIONS OF INTAKE AND EXHAUST PORTS EXHAUST PORTS INTAKE1131 WES YIRST 58 PORTSP151W SOCKIWI CWKH eAST FXt3LIEE IJ Tie tiew dot Electarseic Ss*sJhaearLlghfest Weight Rdy4-Mmt EaghsI New Prop adapter Byrons 4 3 bleded1 props AlE CiupbtFIts Sedi ermglnewItt 718 boh pattern NeEhbg EXfr5 pius shipping 27 00 NOCOT0 Law 200MM tammly RotteN$24995 ness body wheel pants cowl Ship fr Hsnd *43000 Foam wing balsa Included *48000 @phiemaMEeg*ees New 2-piece wieg ewiesIoai 5 Thmupied 34 bIOeZ0zUHIJI 407Dl5 nres OaI Customized front newest Garmsn engines puts Muffler Mount Moemtkig Baits Ptssaure Tsp Smoke ________________________ Carburetor Linksge COI Ignition CII Electroniosi 48 Volt Ignition Peck Safety Swisit SIsflolt Hub Resistor Spark Plugs Year Warrenty Faulty Parts Workmeneh T G MFGU 857 HIgh Moutal Rd North Haled. NJ 07508 274845 Made USA Curtiss Jenny * Quality hand-cut kit complete plans rigging scale control setup wire parts pro-bent custom hardware included parts individually identified packaged Complete decals * Engine sizes 26 50 FS 25 TS * Wing unit removes four screws less 3 minutes flying wires left intact * Superb flight characteristics 15900 VISA e MasterCard Money Order Michigan residents add 4% asiec tax Add *550 P81 US orders $1500 foreign Video Catalog 81500 poet rid VHSIBeta Regular Catalog choice Mini-Plan Hand-Cut Quality Affordable Price AERODROME MODELS LTD j1 Saginaw MI 48603 __517 781-3000 Other Kits Available Aero-Pacer Baby -Pacer Gipey Moth Flybaby Flybaby Combo Hawker Hurricane Jester deny pointed out same drawing published Flygning 1950 officers checked found correct quickly ended investiga tion prototype SAAB Dra ken delta jet unveiled long after wards Karlstrom shown proph et has great deal Bjorn Karlstrom aviation illustration creating space comics impressive achievements very active modeler during 1930s 1940s spe cializing large Scale models such Stin sons Fairchilds 1944 produced FLYG 44 first diesel-engined Free Flight craft Scandinavia exhibit really good flying characteristics Long before 1938 built simple rubberpowered Free Right model used mechanism resembling wide-chord pivot ing wing struts roll control Toward end active building career Karlstrom became popular speak er giving lectures numerous model clubs building small Scale airplanes continues create cutout paper models have appeared About Hobby magazine form inserts Such multifaceted involvement avia tion would have exhausted people Bjom Karlstrom found time yet another role industrial designer drafts man During 1950s 1960s created variety successful vehicle designs also illustrated trucks Scania-Vabis locomotives Motala Verkstad 1952 1965 designed mopeds built Crescent firm pop ular 2000 moped likened critic sculpture designed boats pow ered outboard motors including Pi dinghy 1600 sold Swedish magazine Motor published plans two motorboats Ballerina 50-hp Mercury engine could hit 45 knots nifty little SAAB Sonnett TI sports car body designed Karlstrom went far afield design home freezer streamlined lawn mower Karlstrom achieved formal engineering training gifted eye design methodical mind made up lack lifetime creativ ity has brought rewards 6ther finan cial Karlstrom presented Sod erberg Plaque Swedish Aviation tory Association 1981 received treasured Paul Tissandier Diploma Federation Aeronautique Internationale FAJ next time look set scale drawings notice familiar name bracing Scandinavian ring take mo ment think about man behind pen Now know range depth contribution aviation aeronautical design seeing Bjorn Karlstroms name will conjure up images ice-bound fjords snowshoes glittering craggy peaks Without ever setting foot west ern side Atlantic talented knowledgeable man has great impact people American aviation CL Aerobatics/Fancher Continued page 62 physical point engine/pump senses fuel mass neither above nor below position fuel pickup tube inside tank point end uniflow tube case uniflow tank engine/pump will dis cern no difference between upright inverted flight engine rpm will remain same Given premise made some assumptions developed some theories disassem bled measured both Fox 35 ST 46 engines am familiar verify conclusions first assumed bottom crankcase lower fixed end pump top inside piston upper variable end also assumed volume pump consistent throughout isnt course since upper end composed both uni formly round walls cylinder plus pass area bottom end irregularly shaped lower crankcase bore intake passage crankshaft theorized center pump top bottom would approximate ear defined Center Pumping Action Thi theory complicated fact pum TDC has significantly greater volume BDC theoretical solution dilemm assume CPA would located point midway between average heights thi 168 Model Aviation pump TDC BDC verify theory disassembled Fox measured accurately possible Pump height BDC measured bottom crankshaft web location crankpin top inside piston Pump height TDC calculated adding length piston stroke height BDC Since engine mounts located cen terline crankshaft calculated onehalf diameter backplate opening below engine mount thus dimension subtracted calculated CPA would equal proper height tank fuel pickup uniflow tube location above engine mounts numbers Fox 35 Displacement0352 cu Bore0800 Stroke0700 Diameter backplate open inglOS Pump dimensions Pump depth BDC1 700 Pump depth TDC2400 Average pump depth2050 Calculations Midpoint average pump depth CPA1025 Subtract half backplate openingminus 0525 Height CPA above engine mounts0500 rise surprise Remember just few para graphs back mentioned one-inch-thick Stunt tank mounted same level Fox 35s engine mounts just about guaranteed run equally well both upright inverted Well fuel pickup tube Stunt tank exactly half way up tank golly half inch injust like calculated impressed did same thing ST 46 equivalent set numbers Displacement046 cu Bore0865 Stroke0782 Diameter backplate opening1100 Pump dimensions Pump depth BDC1 787 Pump depth TDC2569 Average pump depth2 180 Calculations Midpoint average pump depthi 090 Subtract half backplate opening0550 Height CPA0540 ST calculations indicate need either thicker tank shimmed off mounts match calculated CPA agrees closely personal experience ST Its interesting note needle valve height ST over 0800 off mount normal inverted-engine installation tank mounted line needle valve engine would run rich inverted lean upright feel conclusions sound could safely used starting place locating tank Unfortunately previously mentioned varia bles volume top bottom ends crankcase make such solution still approxi mate Provision should still made final shimming fine tune run addition CPA very clumsy deter inasmuch requires taking engine apart measuring some dimensions go ing approximate best expecting make precise calculations based ap proximations has simpler way ink Based limited sampling suggest Continued page 173 Youll notice power bargain fuels * Special Detergents Promote clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed FREE SHIPPING ON ORDERS OVER $1500 SIG CHAMPION 2-STROKE FUEL PINT QUART GALLON 0% Nitromethane$1075 5% Nitromethane$365 $525$1275 10% Nitromethane$415 $550$1475 15% Nitromethane$430 $635$1675 25% Nitromethane$515 $795$2195 35% Nitromethane$595 $925$2695 SIGPREMIUM 4-STROKEFUEL 10% Nitromethane$1425 15% Nitromethane$1625 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 995% pure very best grade money can buy also use real 100% pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels con tain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price March 1989 169 Revised Lightweight Dual Spoiler ModuleAT4043 duel spoilers made rigid pvc weigh 3 oz per set closed position total overali height 181 Yi inches modifiable 1 inch unmodified blades fufly extended total overall height h 2% inches modules accuate extremely smooth easily single module 5116 inches thick bv6 inches long Modules can ganged end-to-and longer increased surface area Only *1436 per set Ask local hobby shop today Dealers ask ACE RIC Inc detailsI AL-TEC PRODUCTS INC 18800 St Rt 47E ey OH 45365 513 498-1721 CL Aerobatics/Fancher Continued page 168 align fuel pickup tube uniflow vent top backplate opening starting place case Fox ST old OS Max 35 Stunt calculations actual measurements practical examples worked out within few hundredths inch Since layout almost two-cycle Stunt en gines quite similar should very little variation between engines Users four-cycle engines should determine CPA engines based volume combustion chamber TDC BDC since top end engines produces pumping action hope proves helpful tell body heard Urtnowski Just kidding Windy Please dont send alligators after New subject ST 46 took apart measure foregoing bit belongs young friend Paul Pomposo extremely excited about learning Stunt bought used someone installed new Imitation arrived field couple weeks back Paul already practically worn Out trying start ST Well aint never seen 46 wouldnt run asked him let give try After hour work finally got thing run ning sounded like anemic 049 try ing swing 10 x 6 Top Flite No guts Plus af ter quitting midflight engine extremely hot including lower crankcase Ordinarily bottom end two-cycle en gine should run very cool because expand ing fuel/air mixture constantly runs through Although crankshaft bearing seemed little tight rough didnt seem bad enough cause excessive heat surely something wrong suggested Paul remove engine put toolbox could look later Sure enough upon disassembly problem came obvious previous owner installed cylinder liner turned 1800 its correct po sition exhaust ports aligned take bypass crankcase intake ports aligned exhaust Take look Figure IV depicts gener ic cylinder liner Youll note exhaust ports located higher cylinder wall intake ports very good reason two-cycle engine after combustion takes place piston driven downward until LHC-06 CLEAR SILICONE Ideal areas high vibration Waterproofs insulates Stays soft flexible Use glue seal tanopys wing saddles other areas. SEAL BOAT WATERPROOFPUSHRODS AND RADIO BOXESFITTINGS ATTACH FUEL TANKS TO HULLS AND FUSELAGES Available quality hobby shops everywhere Loctite isa registered trademark Loctite Corporation two things happen very rapid succession First burnt gases expelled second fresh charge fuel/air mixture forced com bustion chamber upcoming compression stroke reason exhaust port opens first high-pressure exhaust gases can expel selves establish flow path out exhaust stack split second later full scavenging exhaust gases completed flow fresh charge chamber charge impacts piston baffle circulates up com bustion chamber back down toward ex haust flushing almost spent charge process case Pauls engine liner installed backwards intake ports will open first thereby allowing high-pressure combus tion gases forced incoming charge both dilutes charge burnt gases heats up bottom end engine result very hot-running engine produces little power extremely hard start fact may run isnt rare might think Pauls fourth example Ive seen modeling career youve got used engine exhibits characteristics check Out Look exhaust port can see intake ports far side obviously higher exhaust ports liner backwards Take apart fix CL Scale/Boss Continued page 63 several suggestions would make visit enjoyable especially anyone going first time museums displays quite impressive over 175 aircraft starts beginning flight first aircraft continues worlds sophisticated aircraft B lA bomber new Modem Flight Gallery cludes some following B-52D AT9 Lock heed YF-12A F4C Phantom II C-47D XB-70 B-58 Hustler PRY Catalina NA X-15A B-26 others Visiting hours 900 am 500 pm weekdays 1000 am 600 pm Satur day Sunday Admission free Stan suggests picture taking have plenty film GOOD flash unit light ing best old seetion muse um excellent new section Also plan make visit two days almost im possible see sections anything less might also note bus service 15 minutes main displays restoration section open adults museum houses airplane flono flyer ROCKET PLANE xP-1 / Only $395 CaIts FunI plus $1/orderGoes up like rocket Ste HGlides down like plane Au Baisa/Ready FiylAttractiveiy Packaged WANTED Distributors ers Increase Profits e Details Jim Masseys Quality Model Products Valley View Dr Box 43 ni 61 37264OBAiiegany NY 14706 March 1989 173 IL@CTITE Teekiqude WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries chargers need packagel Cycler-Charger*19995GO4Wet Cell & Fits 48V Rx 96V Tx packsPlus $5 S&H.ceGelled Cell Others available write call Trickier $2495 CX 4Z% Regular Model$3995 ForPlus $2 S&HFor field kit small Plus $2 S&H Multiple AOelectric boat batteriesSpecify 6 12 24V Radios Heavy Duty Model.$4995 LO sport winch large boat andPlus $250 S&H electric power charging batteriesSpecify 6 1 2V ProductsSASEtorinlormationPO Box 221 CaRa Dealer Inqulnes unitedCanton SD 57013 BOB HOLMAN HAS MORE THAN JUST PLANS Models built plans have won Toledo Best Show World Scale Meet Masters Can other service make claim plans British Magazine also have Most Scale Send $900 two British Plans Books Best Scale catalog F4U-1 EPOXY SMI KIT 75 SPAN TBF-C1 AVENGER EPOXY SMI KIT 82 SPAN Plan Fuselage cowl canopies Best Show Toledo $16195 pp FB VI MOSQUITO 82 SPAN Plan Nacels canopy Spinners Fuselage $19995 p p Plan Fuselage Cowl canopy Ribs Spinner SPITFIRE MKI EPOXY SMI KIT 72 SPAN $17195 pp Plan Fuselage Cowl Canopy Ribs Balsa F6F HELLCAT EPOXY KIT 64 SPAN $19195 pp PLANS Spitfire lA69 Mosquito Fee71 Kit tyhawk 1 A65 P47Thunderbolt . 61 Tempest561 BT-13 Valiant 73 F4U-1 Corsair 61 Harvard .. P-SlBandO61 Fw19OA-460 Btl9Oe61 BtllOc71 F6F-6 Hellcat64 Kawanishi George 64 Spitfire 14 & 19 . 69 OS2U Kingfisher . 56 Gladiator56 Hurricane I70 PLANS $25 EACH OR SHIPPING THE BEST IN SCALE Bob Holman PO Box 741-MA San Bernardino CA 92402 planning build Scale project visit might worthwhile obtain pictures take notes pocket tape recorder handy see firsthand details might incorporate model information call write US Air Force Museum Wright-Patterson AFB OH 45433-6518 Phone 513 255-3284 Documentation source note LF Jim Pepino president Scale Plans Photo Service says new 66-page catalog now available includes photo packs plans three-views Jim provides plan en largement reduction service Photo paeks depending size contain front side rear views plane well close-ups some finer details need landing gear flaps surfaces controls cock pit instrumentation Plan enlarging done using blueprint process Plans available major categories Scale modeling includ ing Control Line course listed RC could candidates conver sion CL wish catalog send $4 SPPS 3209 Madison Ave Greensboro NC 27403 CL Combat/Johnson Continued page 64 Wasp require little work Does kits include just about everything need ex cept adhesive sample kits sent balsa very nicely cut en gine mount assembly put together semi finished model features Voodoo-style leading edge has full-depth spar solid trailing edge just over 400 sq area Profes sional Combat fliers will likely have own fa vorite model wont bother offering slightly less serious Judging lot experience similar models would expect perform well enough place contests does give away foam kill advantage because its solid-wood wing leading edge Oh well get tired patching string cuts foam anyway Does Generix kits calls seem like really good values dollar could fin ished evening recommended super glue Doe holed up palatial estate Ja sonville during winter now would good time get touch him Does Gener tx PO Box Ill Jasonville IN 47438 Prices less $20 Combat kits has sport Stunt kits too What better power new model Nelson 15 examples now come configurations before more-orless standard model rear intake/rear ex haust AAC aluminum/aluminum/chrome piston cylinder constructionRMcM seen domestic foreign FAI Combat models variation engine side-exhaust rear intake original version wtth front intake side exhaust version probably FAI Combat rear intake/rear exhaust model wtth short front end Henry likes confuse other options such ABC liner/piston rather AAC titanium crankshafts just glowengine selection Dont ask about die sels Call Henry Nelson 412 538-5282 infor mation about line sophisticated engines Prices start $175 standard Combat en gine isnt cheapbut theyre best can buy After years battling other en gines Im taking easy way out using Nelson rear intake/rear exhaust AAC setup short nose help cut down weight shorten nose moment models still may win anythingbut Ill look spectac ular losing currently trend Combat model de sign toward rear-set engine prop some close leading edge wing cant get hand hold launch lightweight carbon tail boom has made possible shove engine way back wing such short nose moment model requires long tail moment keep wobbling across sky conventional wood tail booms too heavy made long enough stiff enough resist flying loads result frequently tail-heavy model much fun fly havent seen such model yet just pic ture conventional model boom Drill hole through trailing edge en gine mount Shove carbon fiber arrow shaft some epoxy mount tail feath ers Most modern designs also have controls mounted arrow shaft too small piece aluminum loops around shaft bellcrank bolted seems plenty strong Fast Combat models makes practically indestructible center section also another trend thats away external fuel bladderwhich proba bly good idea Weve found regular Fast Combat bladders work really well skinny tubes models tubing never expands size allowed 1 25-in-diameter tubes use FAI needle setting much better using tubing weve yet break Another plus dont have have special bladders model Cartiers group seems having good luck using open fuel pods models tubing allowed expand whatever size wants claims better performance using style conventional tubing compart ment Greg Hill used two compartments side engine mount equalize dis tribution weight suppose ultimate config uration would having tube front CG behind masses centered middle model know lot guys use outboardlocated fuel ballast lieu adding wing tip weight fuel burns off results plane getting looser lines makes landing thrill Doctor Design claims about nine grams wing tip weight required 48-in-span model offset tendency lines kick outside tip forward plane coming out turn Too much weight sure makes wing cock back turns maybe hes Onto something Wed eyeing Taipan 8 x 6 prop use Fast Combat models hub looked little small performance prop Fox better 8 x 6 wed using threw blade off buzzed up Hoffelt 36R Upon close inspection found air bub bles hub area made up about 30% area gulp failure Tai pan Ive encountered mainly because spun up way above its design limit de sign seems great wed better wait until its available carbon glass Continued page 176 174 Model Aviation
Edition: Model Aviation - 1989/03
Page Numbers: 62, 168, 169, 173, 174
I THOUGHT wed spend time together month talking about couple engine problems received letter few months back Charly Pate Nashville TN Along few nice words about column Nats Charly askd following question What determines fuel tank should placed fuel tank heights referred relationship needle valve ie Set cen ter fuel tank needle valve etc Often tanks location shown plans remember Al Rabe once made fixture allowed him raise lower needle valve hoping coure fine tune engine shimming tank fail ure Sure would like see some comments Youre absolutely right Charly years standard recommendation has line up centerline tank needle valve ever Al others have found doesnt always trick Thus shimming position either tank engine obtain equal engine speeds plane either upright inverted has become necessary nui sance Stunt fliers ception know Fox 35 mounted either upright inverted one-inch-high tank mounted same level will almost always run exactly same both ways seemed clue somewhere put thinking cap re tired personal pondering place Fox 35 hand ST 46 other After consuming substantial sheets paper am ple ration caffeine heres what came up know little two-cycle wonders produce prodigious horsepower might aware secondary function performed engines bottom end ie crankcase area below piston part engine functions very efficient displacement pump performs two tasks First bottom stroke BDC bot tom dead center piston compresses charge fuel air crankcase cylinder bypass/intake ports open charge forced combustion chamber next compression/power-stroke sequence Second top compression stroke TDC top dead center volume beneath piston has enlarged because area sealed increased volume reduces pressure air trapped therein intake port crankshaft opens negative pressure neg ative respect surrounding atmospheric pressure draws air rapidly through venturi past spray bar thereby drawing fuel tank crankcase along Th IS LATED NIDIIAS EIIFIN III SCM NP FIOURE IIIEIKAIRtUIIC 7N CPA.. WNRIC IETERRIRAIIE IF TIE CIffiER IF N1193 ETILTI flow incoming air pumping action al ternately increasing decreasing pressure within crankcase coupled appropriate opening closing exhaust intake ports draws fuel tank rate fuel delivered engine thus determined relationship fuel tank pump trick deter point pump will call Center Pumping Action CPA Continued page 168 Ted just show off graphics capability new toy. er. computer believes hes solved longstanding mystery Stunt technology know position fuel tank engine will run same speed model either upright inverted Hes generated convincing answer months column Figure IV shows intake exhaust ports atypical 2-cycle engine positioned cylinder liner now somebody takes engine apart reassembles cylinder sleeve backwards occurs kind troublesome things happen engine performance including tremendous loss power 62 Model Aviation Conoi Line Aerobatics Ted Fancher 158 Flying Cloud Isle Foster ClAy CA 94404 Gerald Schamp Albany OR built hybrid imltationlOrlental Stunter really beautiful redand-white model Power originally OS 4OFP inadequate planes weight Additional power now comes Tom Lay-tuned ST 60 Closeup Below R shows double horn/double davis arrangement used round adjustment rudder offset RENIH PRESSURE RD EliOt lEE CENTER P119 IEDIT ~1~ ATEC -AIJIIICATER PIN VILE AT MITE OEM CENTER FIGURE IINISIPIESSIREAT IIETE-CVCIIEIIOIE IIF~iI TC9CEMCENTER jAPJ iiiEF Pill IIEIINIT in2Wh AT TIC Ij ATES FliP fLUE ST TEl OEM CENTER Tom Lay T&L Specialties says custombuilt ST 60s produce much power broke arm just starting up Hell still sell you order direct PO Box 6052 Torrance CA 90504 RELATIVE LOCATIONS OF INTAKE AND EXHAUST PORTS EXHAUST PORTS INTAKE1131 WES YIRST 58 PORTSP151W SOCKIWI CWKH eAST FXt3LIEE IJ Tie tiew dot Electarseic Ss*sJhaearLlghfest Weight Rdy4-Mmt EaghsI New Prop adapter Byrons 4 3 bleded1 props AlE CiupbtFIts Sedi ermglnewItt 718 boh pattern NeEhbg EXfr5 pius shipping 27 00 NOCOT0 Law 200MM tammly RotteN$24995 ness body wheel pants cowl Ship fr Hsnd *43000 Foam wing balsa Included *48000 @phiemaMEeg*ees New 2-piece wieg ewiesIoai 5 Thmupied 34 bIOeZ0zUHIJI 407Dl5 nres OaI Customized front newest Garmsn engines puts Muffler Mount Moemtkig Baits Ptssaure Tsp Smoke ________________________ Carburetor Linksge COI Ignition CII Electroniosi 48 Volt Ignition Peck Safety Swisit SIsflolt Hub Resistor Spark Plugs Year Warrenty Faulty Parts Workmeneh T G MFGU 857 HIgh Moutal Rd North Haled. NJ 07508 274845 Made USA Curtiss Jenny * Quality hand-cut kit complete plans rigging scale control setup wire parts pro-bent custom hardware included parts individually identified packaged Complete decals * Engine sizes 26 50 FS 25 TS * Wing unit removes four screws less 3 minutes flying wires left intact * Superb flight characteristics 15900 VISA e MasterCard Money Order Michigan residents add 4% asiec tax Add *550 P81 US orders $1500 foreign Video Catalog 81500 poet rid VHSIBeta Regular Catalog choice Mini-Plan Hand-Cut Quality Affordable Price AERODROME MODELS LTD j1 Saginaw MI 48603 __517 781-3000 Other Kits Available Aero-Pacer Baby -Pacer Gipey Moth Flybaby Flybaby Combo Hawker Hurricane Jester deny pointed out same drawing published Flygning 1950 officers checked found correct quickly ended investiga tion prototype SAAB Dra ken delta jet unveiled long after wards Karlstrom shown proph et has great deal Bjorn Karlstrom aviation illustration creating space comics impressive achievements very active modeler during 1930s 1940s spe cializing large Scale models such Stin sons Fairchilds 1944 produced FLYG 44 first diesel-engined Free Flight craft Scandinavia exhibit really good flying characteristics Long before 1938 built simple rubberpowered Free Right model used mechanism resembling wide-chord pivot ing wing struts roll control Toward end active building career Karlstrom became popular speak er giving lectures numerous model clubs building small Scale airplanes continues create cutout paper models have appeared About Hobby magazine form inserts Such multifaceted involvement avia tion would have exhausted people Bjom Karlstrom found time yet another role industrial designer drafts man During 1950s 1960s created variety successful vehicle designs also illustrated trucks Scania-Vabis locomotives Motala Verkstad 1952 1965 designed mopeds built Crescent firm pop ular 2000 moped likened critic sculpture designed boats pow ered outboard motors including Pi dinghy 1600 sold Swedish magazine Motor published plans two motorboats Ballerina 50-hp Mercury engine could hit 45 knots nifty little SAAB Sonnett TI sports car body designed Karlstrom went far afield design home freezer streamlined lawn mower Karlstrom achieved formal engineering training gifted eye design methodical mind made up lack lifetime creativ ity has brought rewards 6ther finan cial Karlstrom presented Sod erberg Plaque Swedish Aviation tory Association 1981 received treasured Paul Tissandier Diploma Federation Aeronautique Internationale FAJ next time look set scale drawings notice familiar name bracing Scandinavian ring take mo ment think about man behind pen Now know range depth contribution aviation aeronautical design seeing Bjorn Karlstroms name will conjure up images ice-bound fjords snowshoes glittering craggy peaks Without ever setting foot west ern side Atlantic talented knowledgeable man has great impact people American aviation CL Aerobatics/Fancher Continued page 62 physical point engine/pump senses fuel mass neither above nor below position fuel pickup tube inside tank point end uniflow tube case uniflow tank engine/pump will dis cern no difference between upright inverted flight engine rpm will remain same Given premise made some assumptions developed some theories disassem bled measured both Fox 35 ST 46 engines am familiar verify conclusions first assumed bottom crankcase lower fixed end pump top inside piston upper variable end also assumed volume pump consistent throughout isnt course since upper end composed both uni formly round walls cylinder plus pass area bottom end irregularly shaped lower crankcase bore intake passage crankshaft theorized center pump top bottom would approximate ear defined Center Pumping Action Thi theory complicated fact pum TDC has significantly greater volume BDC theoretical solution dilemm assume CPA would located point midway between average heights thi 168 Model Aviation pump TDC BDC verify theory disassembled Fox measured accurately possible Pump height BDC measured bottom crankshaft web location crankpin top inside piston Pump height TDC calculated adding length piston stroke height BDC Since engine mounts located cen terline crankshaft calculated onehalf diameter backplate opening below engine mount thus dimension subtracted calculated CPA would equal proper height tank fuel pickup uniflow tube location above engine mounts numbers Fox 35 Displacement0352 cu Bore0800 Stroke0700 Diameter backplate open inglOS Pump dimensions Pump depth BDC1 700 Pump depth TDC2400 Average pump depth2050 Calculations Midpoint average pump depth CPA1025 Subtract half backplate openingminus 0525 Height CPA above engine mounts0500 rise surprise Remember just few para graphs back mentioned one-inch-thick Stunt tank mounted same level Fox 35s engine mounts just about guaranteed run equally well both upright inverted Well fuel pickup tube Stunt tank exactly half way up tank golly half inch injust like calculated impressed did same thing ST 46 equivalent set numbers Displacement046 cu Bore0865 Stroke0782 Diameter backplate opening1100 Pump dimensions Pump depth BDC1 787 Pump depth TDC2569 Average pump depth2 180 Calculations Midpoint average pump depthi 090 Subtract half backplate opening0550 Height CPA0540 ST calculations indicate need either thicker tank shimmed off mounts match calculated CPA agrees closely personal experience ST Its interesting note needle valve height ST over 0800 off mount normal inverted-engine installation tank mounted line needle valve engine would run rich inverted lean upright feel conclusions sound could safely used starting place locating tank Unfortunately previously mentioned varia bles volume top bottom ends crankcase make such solution still approxi mate Provision should still made final shimming fine tune run addition CPA very clumsy deter inasmuch requires taking engine apart measuring some dimensions go ing approximate best expecting make precise calculations based ap proximations has simpler way ink Based limited sampling suggest Continued page 173 Youll notice power bargain fuels * Special Detergents Promote clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed FREE SHIPPING ON ORDERS OVER $1500 SIG CHAMPION 2-STROKE FUEL PINT QUART GALLON 0% Nitromethane$1075 5% Nitromethane$365 $525$1275 10% Nitromethane$415 $550$1475 15% Nitromethane$430 $635$1675 25% Nitromethane$515 $795$2195 35% Nitromethane$595 $925$2695 SIGPREMIUM 4-STROKEFUEL 10% Nitromethane$1425 15% Nitromethane$1625 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 995% pure very best grade money can buy also use real 100% pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels con tain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price March 1989 169 Revised Lightweight Dual Spoiler ModuleAT4043 duel spoilers made rigid pvc weigh 3 oz per set closed position total overali height 181 Yi inches modifiable 1 inch unmodified blades fufly extended total overall height h 2% inches modules accuate extremely smooth easily single module 5116 inches thick bv6 inches long Modules can ganged end-to-and longer increased surface area Only *1436 per set Ask local hobby shop today Dealers ask ACE RIC Inc detailsI AL-TEC PRODUCTS INC 18800 St Rt 47E ey OH 45365 513 498-1721 CL Aerobatics/Fancher Continued page 168 align fuel pickup tube uniflow vent top backplate opening starting place case Fox ST old OS Max 35 Stunt calculations actual measurements practical examples worked out within few hundredths inch Since layout almost two-cycle Stunt en gines quite similar should very little variation between engines Users four-cycle engines should determine CPA engines based volume combustion chamber TDC BDC since top end engines produces pumping action hope proves helpful tell body heard Urtnowski Just kidding Windy Please dont send alligators after New subject ST 46 took apart measure foregoing bit belongs young friend Paul Pomposo extremely excited about learning Stunt bought used someone installed new Imitation arrived field couple weeks back Paul already practically worn Out trying start ST Well aint never seen 46 wouldnt run asked him let give try After hour work finally got thing run ning sounded like anemic 049 try ing swing 10 x 6 Top Flite No guts Plus af ter quitting midflight engine extremely hot including lower crankcase Ordinarily bottom end two-cycle en gine should run very cool because expand ing fuel/air mixture constantly runs through Although crankshaft bearing seemed little tight rough didnt seem bad enough cause excessive heat surely something wrong suggested Paul remove engine put toolbox could look later Sure enough upon disassembly problem came obvious previous owner installed cylinder liner turned 1800 its correct po sition exhaust ports aligned take bypass crankcase intake ports aligned exhaust Take look Figure IV depicts gener ic cylinder liner Youll note exhaust ports located higher cylinder wall intake ports very good reason two-cycle engine after combustion takes place piston driven downward until LHC-06 CLEAR SILICONE Ideal areas high vibration Waterproofs insulates Stays soft flexible Use glue seal tanopys wing saddles other areas. SEAL BOAT WATERPROOFPUSHRODS AND RADIO BOXESFITTINGS ATTACH FUEL TANKS TO HULLS AND FUSELAGES Available quality hobby shops everywhere Loctite isa registered trademark Loctite Corporation two things happen very rapid succession First burnt gases expelled second fresh charge fuel/air mixture forced com bustion chamber upcoming compression stroke reason exhaust port opens first high-pressure exhaust gases can expel selves establish flow path out exhaust stack split second later full scavenging exhaust gases completed flow fresh charge chamber charge impacts piston baffle circulates up com bustion chamber back down toward ex haust flushing almost spent charge process case Pauls engine liner installed backwards intake ports will open first thereby allowing high-pressure combus tion gases forced incoming charge both dilutes charge burnt gases heats up bottom end engine result very hot-running engine produces little power extremely hard start fact may run isnt rare might think Pauls fourth example Ive seen modeling career youve got used engine exhibits characteristics check Out Look exhaust port can see intake ports far side obviously higher exhaust ports liner backwards Take apart fix CL Scale/Boss Continued page 63 several suggestions would make visit enjoyable especially anyone going first time museums displays quite impressive over 175 aircraft starts beginning flight first aircraft continues worlds sophisticated aircraft B lA bomber new Modem Flight Gallery cludes some following B-52D AT9 Lock heed YF-12A F4C Phantom II C-47D XB-70 B-58 Hustler PRY Catalina NA X-15A B-26 others Visiting hours 900 am 500 pm weekdays 1000 am 600 pm Satur day Sunday Admission free Stan suggests picture taking have plenty film GOOD flash unit light ing best old seetion muse um excellent new section Also plan make visit two days almost im possible see sections anything less might also note bus service 15 minutes main displays restoration section open adults museum houses airplane flono flyer ROCKET PLANE xP-1 / Only $395 CaIts FunI plus $1/orderGoes up like rocket Ste HGlides down like plane Au Baisa/Ready FiylAttractiveiy Packaged WANTED Distributors ers Increase Profits e Details Jim Masseys Quality Model Products Valley View Dr Box 43 ni 61 37264OBAiiegany NY 14706 March 1989 173 IL@CTITE Teekiqude WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries chargers need packagel Cycler-Charger*19995GO4Wet Cell & Fits 48V Rx 96V Tx packsPlus $5 S&H.ceGelled Cell Others available write call Trickier $2495 CX 4Z% Regular Model$3995 ForPlus $2 S&HFor field kit small Plus $2 S&H Multiple AOelectric boat batteriesSpecify 6 12 24V Radios Heavy Duty Model.$4995 LO sport winch large boat andPlus $250 S&H electric power charging batteriesSpecify 6 1 2V ProductsSASEtorinlormationPO Box 221 CaRa Dealer Inqulnes unitedCanton SD 57013 BOB HOLMAN HAS MORE THAN JUST PLANS Models built plans have won Toledo Best Show World Scale Meet Masters Can other service make claim plans British Magazine also have Most Scale Send $900 two British Plans Books Best Scale catalog F4U-1 EPOXY SMI KIT 75 SPAN TBF-C1 AVENGER EPOXY SMI KIT 82 SPAN Plan Fuselage cowl canopies Best Show Toledo $16195 pp FB VI MOSQUITO 82 SPAN Plan Nacels canopy Spinners Fuselage $19995 p p Plan Fuselage Cowl canopy Ribs Spinner SPITFIRE MKI EPOXY SMI KIT 72 SPAN $17195 pp Plan Fuselage Cowl Canopy Ribs Balsa F6F HELLCAT EPOXY KIT 64 SPAN $19195 pp PLANS Spitfire lA69 Mosquito Fee71 Kit tyhawk 1 A65 P47Thunderbolt . 61 Tempest561 BT-13 Valiant 73 F4U-1 Corsair 61 Harvard .. P-SlBandO61 Fw19OA-460 Btl9Oe61 BtllOc71 F6F-6 Hellcat64 Kawanishi George 64 Spitfire 14 & 19 . 69 OS2U Kingfisher . 56 Gladiator56 Hurricane I70 PLANS $25 EACH OR SHIPPING THE BEST IN SCALE Bob Holman PO Box 741-MA San Bernardino CA 92402 planning build Scale project visit might worthwhile obtain pictures take notes pocket tape recorder handy see firsthand details might incorporate model information call write US Air Force Museum Wright-Patterson AFB OH 45433-6518 Phone 513 255-3284 Documentation source note LF Jim Pepino president Scale Plans Photo Service says new 66-page catalog now available includes photo packs plans three-views Jim provides plan en largement reduction service Photo paeks depending size contain front side rear views plane well close-ups some finer details need landing gear flaps surfaces controls cock pit instrumentation Plan enlarging done using blueprint process Plans available major categories Scale modeling includ ing Control Line course listed RC could candidates conver sion CL wish catalog send $4 SPPS 3209 Madison Ave Greensboro NC 27403 CL Combat/Johnson Continued page 64 Wasp require little work Does kits include just about everything need ex cept adhesive sample kits sent balsa very nicely cut en gine mount assembly put together semi finished model features Voodoo-style leading edge has full-depth spar solid trailing edge just over 400 sq area Profes sional Combat fliers will likely have own fa vorite model wont bother offering slightly less serious Judging lot experience similar models would expect perform well enough place contests does give away foam kill advantage because its solid-wood wing leading edge Oh well get tired patching string cuts foam anyway Does Generix kits calls seem like really good values dollar could fin ished evening recommended super glue Doe holed up palatial estate Ja sonville during winter now would good time get touch him Does Gener tx PO Box Ill Jasonville IN 47438 Prices less $20 Combat kits has sport Stunt kits too What better power new model Nelson 15 examples now come configurations before more-orless standard model rear intake/rear ex haust AAC aluminum/aluminum/chrome piston cylinder constructionRMcM seen domestic foreign FAI Combat models variation engine side-exhaust rear intake original version wtth front intake side exhaust version probably FAI Combat rear intake/rear exhaust model wtth short front end Henry likes confuse other options such ABC liner/piston rather AAC titanium crankshafts just glowengine selection Dont ask about die sels Call Henry Nelson 412 538-5282 infor mation about line sophisticated engines Prices start $175 standard Combat en gine isnt cheapbut theyre best can buy After years battling other en gines Im taking easy way out using Nelson rear intake/rear exhaust AAC setup short nose help cut down weight shorten nose moment models still may win anythingbut Ill look spectac ular losing currently trend Combat model de sign toward rear-set engine prop some close leading edge wing cant get hand hold launch lightweight carbon tail boom has made possible shove engine way back wing such short nose moment model requires long tail moment keep wobbling across sky conventional wood tail booms too heavy made long enough stiff enough resist flying loads result frequently tail-heavy model much fun fly havent seen such model yet just pic ture conventional model boom Drill hole through trailing edge en gine mount Shove carbon fiber arrow shaft some epoxy mount tail feath ers Most modern designs also have controls mounted arrow shaft too small piece aluminum loops around shaft bellcrank bolted seems plenty strong Fast Combat models makes practically indestructible center section also another trend thats away external fuel bladderwhich proba bly good idea Weve found regular Fast Combat bladders work really well skinny tubes models tubing never expands size allowed 1 25-in-diameter tubes use FAI needle setting much better using tubing weve yet break Another plus dont have have special bladders model Cartiers group seems having good luck using open fuel pods models tubing allowed expand whatever size wants claims better performance using style conventional tubing compart ment Greg Hill used two compartments side engine mount equalize dis tribution weight suppose ultimate config uration would having tube front CG behind masses centered middle model know lot guys use outboardlocated fuel ballast lieu adding wing tip weight fuel burns off results plane getting looser lines makes landing thrill Doctor Design claims about nine grams wing tip weight required 48-in-span model offset tendency lines kick outside tip forward plane coming out turn Too much weight sure makes wing cock back turns maybe hes Onto something Wed eyeing Taipan 8 x 6 prop use Fast Combat models hub looked little small performance prop Fox better 8 x 6 wed using threw blade off buzzed up Hoffelt 36R Upon close inspection found air bub bles hub area made up about 30% area gulp failure Tai pan Ive encountered mainly because spun up way above its design limit de sign seems great wed better wait until its available carbon glass Continued page 176 174 Model Aviation
Edition: Model Aviation - 1989/03
Page Numbers: 62, 168, 169, 173, 174
I THOUGHT wed spend time together month talking about couple engine problems received letter few months back Charly Pate Nashville TN Along few nice words about column Nats Charly askd following question What determines fuel tank should placed fuel tank heights referred relationship needle valve ie Set cen ter fuel tank needle valve etc Often tanks location shown plans remember Al Rabe once made fixture allowed him raise lower needle valve hoping coure fine tune engine shimming tank fail ure Sure would like see some comments Youre absolutely right Charly years standard recommendation has line up centerline tank needle valve ever Al others have found doesnt always trick Thus shimming position either tank engine obtain equal engine speeds plane either upright inverted has become necessary nui sance Stunt fliers ception know Fox 35 mounted either upright inverted one-inch-high tank mounted same level will almost always run exactly same both ways seemed clue somewhere put thinking cap re tired personal pondering place Fox 35 hand ST 46 other After consuming substantial sheets paper am ple ration caffeine heres what came up know little two-cycle wonders produce prodigious horsepower might aware secondary function performed engines bottom end ie crankcase area below piston part engine functions very efficient displacement pump performs two tasks First bottom stroke BDC bot tom dead center piston compresses charge fuel air crankcase cylinder bypass/intake ports open charge forced combustion chamber next compression/power-stroke sequence Second top compression stroke TDC top dead center volume beneath piston has enlarged because area sealed increased volume reduces pressure air trapped therein intake port crankshaft opens negative pressure neg ative respect surrounding atmospheric pressure draws air rapidly through venturi past spray bar thereby drawing fuel tank crankcase along Th IS LATED NIDIIAS EIIFIN III SCM NP FIOURE IIIEIKAIRtUIIC 7N CPA.. WNRIC IETERRIRAIIE IF TIE CIffiER IF N1193 ETILTI flow incoming air pumping action al ternately increasing decreasing pressure within crankcase coupled appropriate opening closing exhaust intake ports draws fuel tank rate fuel delivered engine thus determined relationship fuel tank pump trick deter point pump will call Center Pumping Action CPA Continued page 168 Ted just show off graphics capability new toy. er. computer believes hes solved longstanding mystery Stunt technology know position fuel tank engine will run same speed model either upright inverted Hes generated convincing answer months column Figure IV shows intake exhaust ports atypical 2-cycle engine positioned cylinder liner now somebody takes engine apart reassembles cylinder sleeve backwards occurs kind troublesome things happen engine performance including tremendous loss power 62 Model Aviation Conoi Line Aerobatics Ted Fancher 158 Flying Cloud Isle Foster ClAy CA 94404 Gerald Schamp Albany OR built hybrid imltationlOrlental Stunter really beautiful redand-white model Power originally OS 4OFP inadequate planes weight Additional power now comes Tom Lay-tuned ST 60 Closeup Below R shows double horn/double davis arrangement used round adjustment rudder offset RENIH PRESSURE RD EliOt lEE CENTER P119 IEDIT ~1~ ATEC -AIJIIICATER PIN VILE AT MITE OEM CENTER FIGURE IINISIPIESSIREAT IIETE-CVCIIEIIOIE IIF~iI TC9CEMCENTER jAPJ iiiEF Pill IIEIINIT in2Wh AT TIC Ij ATES FliP fLUE ST TEl OEM CENTER Tom Lay T&L Specialties says custombuilt ST 60s produce much power broke arm just starting up Hell still sell you order direct PO Box 6052 Torrance CA 90504 RELATIVE LOCATIONS OF INTAKE AND EXHAUST PORTS EXHAUST PORTS INTAKE1131 WES YIRST 58 PORTSP151W SOCKIWI CWKH eAST FXt3LIEE IJ Tie tiew dot Electarseic Ss*sJhaearLlghfest Weight Rdy4-Mmt EaghsI New Prop adapter Byrons 4 3 bleded1 props AlE CiupbtFIts Sedi ermglnewItt 718 boh pattern NeEhbg EXfr5 pius shipping 27 00 NOCOT0 Law 200MM tammly RotteN$24995 ness body wheel pants cowl Ship fr Hsnd *43000 Foam wing balsa Included *48000 @phiemaMEeg*ees New 2-piece wieg ewiesIoai 5 Thmupied 34 bIOeZ0zUHIJI 407Dl5 nres OaI Customized front newest Garmsn engines puts Muffler Mount Moemtkig Baits Ptssaure Tsp Smoke ________________________ Carburetor Linksge COI Ignition CII Electroniosi 48 Volt Ignition Peck Safety Swisit SIsflolt Hub Resistor Spark Plugs Year Warrenty Faulty Parts Workmeneh T G MFGU 857 HIgh Moutal Rd North Haled. NJ 07508 274845 Made USA Curtiss Jenny * Quality hand-cut kit complete plans rigging scale control setup wire parts pro-bent custom hardware included parts individually identified packaged Complete decals * Engine sizes 26 50 FS 25 TS * Wing unit removes four screws less 3 minutes flying wires left intact * Superb flight characteristics 15900 VISA e MasterCard Money Order Michigan residents add 4% asiec tax Add *550 P81 US orders $1500 foreign Video Catalog 81500 poet rid VHSIBeta Regular Catalog choice Mini-Plan Hand-Cut Quality Affordable Price AERODROME MODELS LTD j1 Saginaw MI 48603 __517 781-3000 Other Kits Available Aero-Pacer Baby -Pacer Gipey Moth Flybaby Flybaby Combo Hawker Hurricane Jester deny pointed out same drawing published Flygning 1950 officers checked found correct quickly ended investiga tion prototype SAAB Dra ken delta jet unveiled long after wards Karlstrom shown proph et has great deal Bjorn Karlstrom aviation illustration creating space comics impressive achievements very active modeler during 1930s 1940s spe cializing large Scale models such Stin sons Fairchilds 1944 produced FLYG 44 first diesel-engined Free Flight craft Scandinavia exhibit really good flying characteristics Long before 1938 built simple rubberpowered Free Right model used mechanism resembling wide-chord pivot ing wing struts roll control Toward end active building career Karlstrom became popular speak er giving lectures numerous model clubs building small Scale airplanes continues create cutout paper models have appeared About Hobby magazine form inserts Such multifaceted involvement avia tion would have exhausted people Bjom Karlstrom found time yet another role industrial designer drafts man During 1950s 1960s created variety successful vehicle designs also illustrated trucks Scania-Vabis locomotives Motala Verkstad 1952 1965 designed mopeds built Crescent firm pop ular 2000 moped likened critic sculpture designed boats pow ered outboard motors including Pi dinghy 1600 sold Swedish magazine Motor published plans two motorboats Ballerina 50-hp Mercury engine could hit 45 knots nifty little SAAB Sonnett TI sports car body designed Karlstrom went far afield design home freezer streamlined lawn mower Karlstrom achieved formal engineering training gifted eye design methodical mind made up lack lifetime creativ ity has brought rewards 6ther finan cial Karlstrom presented Sod erberg Plaque Swedish Aviation tory Association 1981 received treasured Paul Tissandier Diploma Federation Aeronautique Internationale FAJ next time look set scale drawings notice familiar name bracing Scandinavian ring take mo ment think about man behind pen Now know range depth contribution aviation aeronautical design seeing Bjorn Karlstroms name will conjure up images ice-bound fjords snowshoes glittering craggy peaks Without ever setting foot west ern side Atlantic talented knowledgeable man has great impact people American aviation CL Aerobatics/Fancher Continued page 62 physical point engine/pump senses fuel mass neither above nor below position fuel pickup tube inside tank point end uniflow tube case uniflow tank engine/pump will dis cern no difference between upright inverted flight engine rpm will remain same Given premise made some assumptions developed some theories disassem bled measured both Fox 35 ST 46 engines am familiar verify conclusions first assumed bottom crankcase lower fixed end pump top inside piston upper variable end also assumed volume pump consistent throughout isnt course since upper end composed both uni formly round walls cylinder plus pass area bottom end irregularly shaped lower crankcase bore intake passage crankshaft theorized center pump top bottom would approximate ear defined Center Pumping Action Thi theory complicated fact pum TDC has significantly greater volume BDC theoretical solution dilemm assume CPA would located point midway between average heights thi 168 Model Aviation pump TDC BDC verify theory disassembled Fox measured accurately possible Pump height BDC measured bottom crankshaft web location crankpin top inside piston Pump height TDC calculated adding length piston stroke height BDC Since engine mounts located cen terline crankshaft calculated onehalf diameter backplate opening below engine mount thus dimension subtracted calculated CPA would equal proper height tank fuel pickup uniflow tube location above engine mounts numbers Fox 35 Displacement0352 cu Bore0800 Stroke0700 Diameter backplate open inglOS Pump dimensions Pump depth BDC1 700 Pump depth TDC2400 Average pump depth2050 Calculations Midpoint average pump depth CPA1025 Subtract half backplate openingminus 0525 Height CPA above engine mounts0500 rise surprise Remember just few para graphs back mentioned one-inch-thick Stunt tank mounted same level Fox 35s engine mounts just about guaranteed run equally well both upright inverted Well fuel pickup tube Stunt tank exactly half way up tank golly half inch injust like calculated impressed did same thing ST 46 equivalent set numbers Displacement046 cu Bore0865 Stroke0782 Diameter backplate opening1100 Pump dimensions Pump depth BDC1 787 Pump depth TDC2569 Average pump depth2 180 Calculations Midpoint average pump depthi 090 Subtract half backplate opening0550 Height CPA0540 ST calculations indicate need either thicker tank shimmed off mounts match calculated CPA agrees closely personal experience ST Its interesting note needle valve height ST over 0800 off mount normal inverted-engine installation tank mounted line needle valve engine would run rich inverted lean upright feel conclusions sound could safely used starting place locating tank Unfortunately previously mentioned varia bles volume top bottom ends crankcase make such solution still approxi mate Provision should still made final shimming fine tune run addition CPA very clumsy deter inasmuch requires taking engine apart measuring some dimensions go ing approximate best expecting make precise calculations based ap proximations has simpler way ink Based limited sampling suggest Continued page 173 Youll notice power bargain fuels * Special Detergents Promote clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed FREE SHIPPING ON ORDERS OVER $1500 SIG CHAMPION 2-STROKE FUEL PINT QUART GALLON 0% Nitromethane$1075 5% Nitromethane$365 $525$1275 10% Nitromethane$415 $550$1475 15% Nitromethane$430 $635$1675 25% Nitromethane$515 $795$2195 35% Nitromethane$595 $925$2695 SIGPREMIUM 4-STROKEFUEL 10% Nitromethane$1425 15% Nitromethane$1625 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 995% pure very best grade money can buy also use real 100% pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels con tain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price March 1989 169 Revised Lightweight Dual Spoiler ModuleAT4043 duel spoilers made rigid pvc weigh 3 oz per set closed position total overali height 181 Yi inches modifiable 1 inch unmodified blades fufly extended total overall height h 2% inches modules accuate extremely smooth easily single module 5116 inches thick bv6 inches long Modules can ganged end-to-and longer increased surface area Only *1436 per set Ask local hobby shop today Dealers ask ACE RIC Inc detailsI AL-TEC PRODUCTS INC 18800 St Rt 47E ey OH 45365 513 498-1721 CL Aerobatics/Fancher Continued page 168 align fuel pickup tube uniflow vent top backplate opening starting place case Fox ST old OS Max 35 Stunt calculations actual measurements practical examples worked out within few hundredths inch Since layout almost two-cycle Stunt en gines quite similar should very little variation between engines Users four-cycle engines should determine CPA engines based volume combustion chamber TDC BDC since top end engines produces pumping action hope proves helpful tell body heard Urtnowski Just kidding Windy Please dont send alligators after New subject ST 46 took apart measure foregoing bit belongs young friend Paul Pomposo extremely excited about learning Stunt bought used someone installed new Imitation arrived field couple weeks back Paul already practically worn Out trying start ST Well aint never seen 46 wouldnt run asked him let give try After hour work finally got thing run ning sounded like anemic 049 try ing swing 10 x 6 Top Flite No guts Plus af ter quitting midflight engine extremely hot including lower crankcase Ordinarily bottom end two-cycle en gine should run very cool because expand ing fuel/air mixture constantly runs through Although crankshaft bearing seemed little tight rough didnt seem bad enough cause excessive heat surely something wrong suggested Paul remove engine put toolbox could look later Sure enough upon disassembly problem came obvious previous owner installed cylinder liner turned 1800 its correct po sition exhaust ports aligned take bypass crankcase intake ports aligned exhaust Take look Figure IV depicts gener ic cylinder liner Youll note exhaust ports located higher cylinder wall intake ports very good reason two-cycle engine after combustion takes place piston driven downward until LHC-06 CLEAR SILICONE Ideal areas high vibration Waterproofs insulates Stays soft flexible Use glue seal tanopys wing saddles other areas. SEAL BOAT WATERPROOFPUSHRODS AND RADIO BOXESFITTINGS ATTACH FUEL TANKS TO HULLS AND FUSELAGES Available quality hobby shops everywhere Loctite isa registered trademark Loctite Corporation two things happen very rapid succession First burnt gases expelled second fresh charge fuel/air mixture forced com bustion chamber upcoming compression stroke reason exhaust port opens first high-pressure exhaust gases can expel selves establish flow path out exhaust stack split second later full scavenging exhaust gases completed flow fresh charge chamber charge impacts piston baffle circulates up com bustion chamber back down toward ex haust flushing almost spent charge process case Pauls engine liner installed backwards intake ports will open first thereby allowing high-pressure combus tion gases forced incoming charge both dilutes charge burnt gases heats up bottom end engine result very hot-running engine produces little power extremely hard start fact may run isnt rare might think Pauls fourth example Ive seen modeling career youve got used engine exhibits characteristics check Out Look exhaust port can see intake ports far side obviously higher exhaust ports liner backwards Take apart fix CL Scale/Boss Continued page 63 several suggestions would make visit enjoyable especially anyone going first time museums displays quite impressive over 175 aircraft starts beginning flight first aircraft continues worlds sophisticated aircraft B lA bomber new Modem Flight Gallery cludes some following B-52D AT9 Lock heed YF-12A F4C Phantom II C-47D XB-70 B-58 Hustler PRY Catalina NA X-15A B-26 others Visiting hours 900 am 500 pm weekdays 1000 am 600 pm Satur day Sunday Admission free Stan suggests picture taking have plenty film GOOD flash unit light ing best old seetion muse um excellent new section Also plan make visit two days almost im possible see sections anything less might also note bus service 15 minutes main displays restoration section open adults museum houses airplane flono flyer ROCKET PLANE xP-1 / Only $395 CaIts FunI plus $1/orderGoes up like rocket Ste HGlides down like plane Au Baisa/Ready FiylAttractiveiy Packaged WANTED Distributors ers Increase Profits e Details Jim Masseys Quality Model Products Valley View Dr Box 43 ni 61 37264OBAiiegany NY 14706 March 1989 173 IL@CTITE Teekiqude WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries chargers need packagel Cycler-Charger*19995GO4Wet Cell & Fits 48V Rx 96V Tx packsPlus $5 S&H.ceGelled Cell Others available write call Trickier $2495 CX 4Z% Regular Model$3995 ForPlus $2 S&HFor field kit small Plus $2 S&H Multiple AOelectric boat batteriesSpecify 6 12 24V Radios Heavy Duty Model.$4995 LO sport winch large boat andPlus $250 S&H electric power charging batteriesSpecify 6 1 2V ProductsSASEtorinlormationPO Box 221 CaRa Dealer Inqulnes unitedCanton SD 57013 BOB HOLMAN HAS MORE THAN JUST PLANS Models built plans have won Toledo Best Show World Scale Meet Masters Can other service make claim plans British Magazine also have Most Scale Send $900 two British Plans Books Best Scale catalog F4U-1 EPOXY SMI KIT 75 SPAN TBF-C1 AVENGER EPOXY SMI KIT 82 SPAN Plan Fuselage cowl canopies Best Show Toledo $16195 pp FB VI MOSQUITO 82 SPAN Plan Nacels canopy Spinners Fuselage $19995 p p Plan Fuselage Cowl canopy Ribs Spinner SPITFIRE MKI EPOXY SMI KIT 72 SPAN $17195 pp Plan Fuselage Cowl Canopy Ribs Balsa F6F HELLCAT EPOXY KIT 64 SPAN $19195 pp PLANS Spitfire lA69 Mosquito Fee71 Kit tyhawk 1 A65 P47Thunderbolt . 61 Tempest561 BT-13 Valiant 73 F4U-1 Corsair 61 Harvard .. P-SlBandO61 Fw19OA-460 Btl9Oe61 BtllOc71 F6F-6 Hellcat64 Kawanishi George 64 Spitfire 14 & 19 . 69 OS2U Kingfisher . 56 Gladiator56 Hurricane I70 PLANS $25 EACH OR SHIPPING THE BEST IN SCALE Bob Holman PO Box 741-MA San Bernardino CA 92402 planning build Scale project visit might worthwhile obtain pictures take notes pocket tape recorder handy see firsthand details might incorporate model information call write US Air Force Museum Wright-Patterson AFB OH 45433-6518 Phone 513 255-3284 Documentation source note LF Jim Pepino president Scale Plans Photo Service says new 66-page catalog now available includes photo packs plans three-views Jim provides plan en largement reduction service Photo paeks depending size contain front side rear views plane well close-ups some finer details need landing gear flaps surfaces controls cock pit instrumentation Plan enlarging done using blueprint process Plans available major categories Scale modeling includ ing Control Line course listed RC could candidates conver sion CL wish catalog send $4 SPPS 3209 Madison Ave Greensboro NC 27403 CL Combat/Johnson Continued page 64 Wasp require little work Does kits include just about everything need ex cept adhesive sample kits sent balsa very nicely cut en gine mount assembly put together semi finished model features Voodoo-style leading edge has full-depth spar solid trailing edge just over 400 sq area Profes sional Combat fliers will likely have own fa vorite model wont bother offering slightly less serious Judging lot experience similar models would expect perform well enough place contests does give away foam kill advantage because its solid-wood wing leading edge Oh well get tired patching string cuts foam anyway Does Generix kits calls seem like really good values dollar could fin ished evening recommended super glue Doe holed up palatial estate Ja sonville during winter now would good time get touch him Does Gener tx PO Box Ill Jasonville IN 47438 Prices less $20 Combat kits has sport Stunt kits too What better power new model Nelson 15 examples now come configurations before more-orless standard model rear intake/rear ex haust AAC aluminum/aluminum/chrome piston cylinder constructionRMcM seen domestic foreign FAI Combat models variation engine side-exhaust rear intake original version wtth front intake side exhaust version probably FAI Combat rear intake/rear exhaust model wtth short front end Henry likes confuse other options such ABC liner/piston rather AAC titanium crankshafts just glowengine selection Dont ask about die sels Call Henry Nelson 412 538-5282 infor mation about line sophisticated engines Prices start $175 standard Combat en gine isnt cheapbut theyre best can buy After years battling other en gines Im taking easy way out using Nelson rear intake/rear exhaust AAC setup short nose help cut down weight shorten nose moment models still may win anythingbut Ill look spectac ular losing currently trend Combat model de sign toward rear-set engine prop some close leading edge wing cant get hand hold launch lightweight carbon tail boom has made possible shove engine way back wing such short nose moment model requires long tail moment keep wobbling across sky conventional wood tail booms too heavy made long enough stiff enough resist flying loads result frequently tail-heavy model much fun fly havent seen such model yet just pic ture conventional model boom Drill hole through trailing edge en gine mount Shove carbon fiber arrow shaft some epoxy mount tail feath ers Most modern designs also have controls mounted arrow shaft too small piece aluminum loops around shaft bellcrank bolted seems plenty strong Fast Combat models makes practically indestructible center section also another trend thats away external fuel bladderwhich proba bly good idea Weve found regular Fast Combat bladders work really well skinny tubes models tubing never expands size allowed 1 25-in-diameter tubes use FAI needle setting much better using tubing weve yet break Another plus dont have have special bladders model Cartiers group seems having good luck using open fuel pods models tubing allowed expand whatever size wants claims better performance using style conventional tubing compart ment Greg Hill used two compartments side engine mount equalize dis tribution weight suppose ultimate config uration would having tube front CG behind masses centered middle model know lot guys use outboardlocated fuel ballast lieu adding wing tip weight fuel burns off results plane getting looser lines makes landing thrill Doctor Design claims about nine grams wing tip weight required 48-in-span model offset tendency lines kick outside tip forward plane coming out turn Too much weight sure makes wing cock back turns maybe hes Onto something Wed eyeing Taipan 8 x 6 prop use Fast Combat models hub looked little small performance prop Fox better 8 x 6 wed using threw blade off buzzed up Hoffelt 36R Upon close inspection found air bub bles hub area made up about 30% area gulp failure Tai pan Ive encountered mainly because spun up way above its design limit de sign seems great wed better wait until its available carbon glass Continued page 176 174 Model Aviation
Edition: Model Aviation - 1989/03
Page Numbers: 62, 168, 169, 173, 174
I THOUGHT wed spend time together month talking about couple engine problems received letter few months back Charly Pate Nashville TN Along few nice words about column Nats Charly askd following question What determines fuel tank should placed fuel tank heights referred relationship needle valve ie Set cen ter fuel tank needle valve etc Often tanks location shown plans remember Al Rabe once made fixture allowed him raise lower needle valve hoping coure fine tune engine shimming tank fail ure Sure would like see some comments Youre absolutely right Charly years standard recommendation has line up centerline tank needle valve ever Al others have found doesnt always trick Thus shimming position either tank engine obtain equal engine speeds plane either upright inverted has become necessary nui sance Stunt fliers ception know Fox 35 mounted either upright inverted one-inch-high tank mounted same level will almost always run exactly same both ways seemed clue somewhere put thinking cap re tired personal pondering place Fox 35 hand ST 46 other After consuming substantial sheets paper am ple ration caffeine heres what came up know little two-cycle wonders produce prodigious horsepower might aware secondary function performed engines bottom end ie crankcase area below piston part engine functions very efficient displacement pump performs two tasks First bottom stroke BDC bot tom dead center piston compresses charge fuel air crankcase cylinder bypass/intake ports open charge forced combustion chamber next compression/power-stroke sequence Second top compression stroke TDC top dead center volume beneath piston has enlarged because area sealed increased volume reduces pressure air trapped therein intake port crankshaft opens negative pressure neg ative respect surrounding atmospheric pressure draws air rapidly through venturi past spray bar thereby drawing fuel tank crankcase along Th IS LATED NIDIIAS EIIFIN III SCM NP FIOURE IIIEIKAIRtUIIC 7N CPA.. WNRIC IETERRIRAIIE IF TIE CIffiER IF N1193 ETILTI flow incoming air pumping action al ternately increasing decreasing pressure within crankcase coupled appropriate opening closing exhaust intake ports draws fuel tank rate fuel delivered engine thus determined relationship fuel tank pump trick deter point pump will call Center Pumping Action CPA Continued page 168 Ted just show off graphics capability new toy. er. computer believes hes solved longstanding mystery Stunt technology know position fuel tank engine will run same speed model either upright inverted Hes generated convincing answer months column Figure IV shows intake exhaust ports atypical 2-cycle engine positioned cylinder liner now somebody takes engine apart reassembles cylinder sleeve backwards occurs kind troublesome things happen engine performance including tremendous loss power 62 Model Aviation Conoi Line Aerobatics Ted Fancher 158 Flying Cloud Isle Foster ClAy CA 94404 Gerald Schamp Albany OR built hybrid imltationlOrlental Stunter really beautiful redand-white model Power originally OS 4OFP inadequate planes weight Additional power now comes Tom Lay-tuned ST 60 Closeup Below R shows double horn/double davis arrangement used round adjustment rudder offset RENIH PRESSURE RD EliOt lEE CENTER P119 IEDIT ~1~ ATEC -AIJIIICATER PIN VILE AT MITE OEM CENTER FIGURE IINISIPIESSIREAT IIETE-CVCIIEIIOIE IIF~iI TC9CEMCENTER jAPJ iiiEF Pill IIEIINIT in2Wh AT TIC Ij ATES FliP fLUE ST TEl OEM CENTER Tom Lay T&L Specialties says custombuilt ST 60s produce much power broke arm just starting up Hell still sell you order direct PO Box 6052 Torrance CA 90504 RELATIVE LOCATIONS OF INTAKE AND EXHAUST PORTS EXHAUST PORTS INTAKE1131 WES YIRST 58 PORTSP151W SOCKIWI CWKH eAST FXt3LIEE IJ Tie tiew dot Electarseic Ss*sJhaearLlghfest Weight Rdy4-Mmt EaghsI New Prop adapter Byrons 4 3 bleded1 props AlE CiupbtFIts Sedi ermglnewItt 718 boh pattern NeEhbg EXfr5 pius shipping 27 00 NOCOT0 Law 200MM tammly RotteN$24995 ness body wheel pants cowl Ship fr Hsnd *43000 Foam wing balsa Included *48000 @phiemaMEeg*ees New 2-piece wieg ewiesIoai 5 Thmupied 34 bIOeZ0zUHIJI 407Dl5 nres OaI Customized front newest Garmsn engines puts Muffler Mount Moemtkig Baits Ptssaure Tsp Smoke ________________________ Carburetor Linksge COI Ignition CII Electroniosi 48 Volt Ignition Peck Safety Swisit SIsflolt Hub Resistor Spark Plugs Year Warrenty Faulty Parts Workmeneh T G MFGU 857 HIgh Moutal Rd North Haled. NJ 07508 274845 Made USA Curtiss Jenny * Quality hand-cut kit complete plans rigging scale control setup wire parts pro-bent custom hardware included parts individually identified packaged Complete decals * Engine sizes 26 50 FS 25 TS * Wing unit removes four screws less 3 minutes flying wires left intact * Superb flight characteristics 15900 VISA e MasterCard Money Order Michigan residents add 4% asiec tax Add *550 P81 US orders $1500 foreign Video Catalog 81500 poet rid VHSIBeta Regular Catalog choice Mini-Plan Hand-Cut Quality Affordable Price AERODROME MODELS LTD j1 Saginaw MI 48603 __517 781-3000 Other Kits Available Aero-Pacer Baby -Pacer Gipey Moth Flybaby Flybaby Combo Hawker Hurricane Jester deny pointed out same drawing published Flygning 1950 officers checked found correct quickly ended investiga tion prototype SAAB Dra ken delta jet unveiled long after wards Karlstrom shown proph et has great deal Bjorn Karlstrom aviation illustration creating space comics impressive achievements very active modeler during 1930s 1940s spe cializing large Scale models such Stin sons Fairchilds 1944 produced FLYG 44 first diesel-engined Free Flight craft Scandinavia exhibit really good flying characteristics Long before 1938 built simple rubberpowered Free Right model used mechanism resembling wide-chord pivot ing wing struts roll control Toward end active building career Karlstrom became popular speak er giving lectures numerous model clubs building small Scale airplanes continues create cutout paper models have appeared About Hobby magazine form inserts Such multifaceted involvement avia tion would have exhausted people Bjom Karlstrom found time yet another role industrial designer drafts man During 1950s 1960s created variety successful vehicle designs also illustrated trucks Scania-Vabis locomotives Motala Verkstad 1952 1965 designed mopeds built Crescent firm pop ular 2000 moped likened critic sculpture designed boats pow ered outboard motors including Pi dinghy 1600 sold Swedish magazine Motor published plans two motorboats Ballerina 50-hp Mercury engine could hit 45 knots nifty little SAAB Sonnett TI sports car body designed Karlstrom went far afield design home freezer streamlined lawn mower Karlstrom achieved formal engineering training gifted eye design methodical mind made up lack lifetime creativ ity has brought rewards 6ther finan cial Karlstrom presented Sod erberg Plaque Swedish Aviation tory Association 1981 received treasured Paul Tissandier Diploma Federation Aeronautique Internationale FAJ next time look set scale drawings notice familiar name bracing Scandinavian ring take mo ment think about man behind pen Now know range depth contribution aviation aeronautical design seeing Bjorn Karlstroms name will conjure up images ice-bound fjords snowshoes glittering craggy peaks Without ever setting foot west ern side Atlantic talented knowledgeable man has great impact people American aviation CL Aerobatics/Fancher Continued page 62 physical point engine/pump senses fuel mass neither above nor below position fuel pickup tube inside tank point end uniflow tube case uniflow tank engine/pump will dis cern no difference between upright inverted flight engine rpm will remain same Given premise made some assumptions developed some theories disassem bled measured both Fox 35 ST 46 engines am familiar verify conclusions first assumed bottom crankcase lower fixed end pump top inside piston upper variable end also assumed volume pump consistent throughout isnt course since upper end composed both uni formly round walls cylinder plus pass area bottom end irregularly shaped lower crankcase bore intake passage crankshaft theorized center pump top bottom would approximate ear defined Center Pumping Action Thi theory complicated fact pum TDC has significantly greater volume BDC theoretical solution dilemm assume CPA would located point midway between average heights thi 168 Model Aviation pump TDC BDC verify theory disassembled Fox measured accurately possible Pump height BDC measured bottom crankshaft web location crankpin top inside piston Pump height TDC calculated adding length piston stroke height BDC Since engine mounts located cen terline crankshaft calculated onehalf diameter backplate opening below engine mount thus dimension subtracted calculated CPA would equal proper height tank fuel pickup uniflow tube location above engine mounts numbers Fox 35 Displacement0352 cu Bore0800 Stroke0700 Diameter backplate open inglOS Pump dimensions Pump depth BDC1 700 Pump depth TDC2400 Average pump depth2050 Calculations Midpoint average pump depth CPA1025 Subtract half backplate openingminus 0525 Height CPA above engine mounts0500 rise surprise Remember just few para graphs back mentioned one-inch-thick Stunt tank mounted same level Fox 35s engine mounts just about guaranteed run equally well both upright inverted Well fuel pickup tube Stunt tank exactly half way up tank golly half inch injust like calculated impressed did same thing ST 46 equivalent set numbers Displacement046 cu Bore0865 Stroke0782 Diameter backplate opening1100 Pump dimensions Pump depth BDC1 787 Pump depth TDC2569 Average pump depth2 180 Calculations Midpoint average pump depthi 090 Subtract half backplate opening0550 Height CPA0540 ST calculations indicate need either thicker tank shimmed off mounts match calculated CPA agrees closely personal experience ST Its interesting note needle valve height ST over 0800 off mount normal inverted-engine installation tank mounted line needle valve engine would run rich inverted lean upright feel conclusions sound could safely used starting place locating tank Unfortunately previously mentioned varia bles volume top bottom ends crankcase make such solution still approxi mate Provision should still made final shimming fine tune run addition CPA very clumsy deter inasmuch requires taking engine apart measuring some dimensions go ing approximate best expecting make precise calculations based ap proximations has simpler way ink Based limited sampling suggest Continued page 173 Youll notice power bargain fuels * Special Detergents Promote clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed FREE SHIPPING ON ORDERS OVER $1500 SIG CHAMPION 2-STROKE FUEL PINT QUART GALLON 0% Nitromethane$1075 5% Nitromethane$365 $525$1275 10% Nitromethane$415 $550$1475 15% Nitromethane$430 $635$1675 25% Nitromethane$515 $795$2195 35% Nitromethane$595 $925$2695 SIGPREMIUM 4-STROKEFUEL 10% Nitromethane$1425 15% Nitromethane$1625 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 995% pure very best grade money can buy also use real 100% pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels con tain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price March 1989 169 Revised Lightweight Dual Spoiler ModuleAT4043 duel spoilers made rigid pvc weigh 3 oz per set closed position total overali height 181 Yi inches modifiable 1 inch unmodified blades fufly extended total overall height h 2% inches modules accuate extremely smooth easily single module 5116 inches thick bv6 inches long Modules can ganged end-to-and longer increased surface area Only *1436 per set Ask local hobby shop today Dealers ask ACE RIC Inc detailsI AL-TEC PRODUCTS INC 18800 St Rt 47E ey OH 45365 513 498-1721 CL Aerobatics/Fancher Continued page 168 align fuel pickup tube uniflow vent top backplate opening starting place case Fox ST old OS Max 35 Stunt calculations actual measurements practical examples worked out within few hundredths inch Since layout almost two-cycle Stunt en gines quite similar should very little variation between engines Users four-cycle engines should determine CPA engines based volume combustion chamber TDC BDC since top end engines produces pumping action hope proves helpful tell body heard Urtnowski Just kidding Windy Please dont send alligators after New subject ST 46 took apart measure foregoing bit belongs young friend Paul Pomposo extremely excited about learning Stunt bought used someone installed new Imitation arrived field couple weeks back Paul already practically worn Out trying start ST Well aint never seen 46 wouldnt run asked him let give try After hour work finally got thing run ning sounded like anemic 049 try ing swing 10 x 6 Top Flite No guts Plus af ter quitting midflight engine extremely hot including lower crankcase Ordinarily bottom end two-cycle en gine should run very cool because expand ing fuel/air mixture constantly runs through Although crankshaft bearing seemed little tight rough didnt seem bad enough cause excessive heat surely something wrong suggested Paul remove engine put toolbox could look later Sure enough upon disassembly problem came obvious previous owner installed cylinder liner turned 1800 its correct po sition exhaust ports aligned take bypass crankcase intake ports aligned exhaust Take look Figure IV depicts gener ic cylinder liner Youll note exhaust ports located higher cylinder wall intake ports very good reason two-cycle engine after combustion takes place piston driven downward until LHC-06 CLEAR SILICONE Ideal areas high vibration Waterproofs insulates Stays soft flexible Use glue seal tanopys wing saddles other areas. SEAL BOAT WATERPROOFPUSHRODS AND RADIO BOXESFITTINGS ATTACH FUEL TANKS TO HULLS AND FUSELAGES Available quality hobby shops everywhere Loctite isa registered trademark Loctite Corporation two things happen very rapid succession First burnt gases expelled second fresh charge fuel/air mixture forced com bustion chamber upcoming compression stroke reason exhaust port opens first high-pressure exhaust gases can expel selves establish flow path out exhaust stack split second later full scavenging exhaust gases completed flow fresh charge chamber charge impacts piston baffle circulates up com bustion chamber back down toward ex haust flushing almost spent charge process case Pauls engine liner installed backwards intake ports will open first thereby allowing high-pressure combus tion gases forced incoming charge both dilutes charge burnt gases heats up bottom end engine result very hot-running engine produces little power extremely hard start fact may run isnt rare might think Pauls fourth example Ive seen modeling career youve got used engine exhibits characteristics check Out Look exhaust port can see intake ports far side obviously higher exhaust ports liner backwards Take apart fix CL Scale/Boss Continued page 63 several suggestions would make visit enjoyable especially anyone going first time museums displays quite impressive over 175 aircraft starts beginning flight first aircraft continues worlds sophisticated aircraft B lA bomber new Modem Flight Gallery cludes some following B-52D AT9 Lock heed YF-12A F4C Phantom II C-47D XB-70 B-58 Hustler PRY Catalina NA X-15A B-26 others Visiting hours 900 am 500 pm weekdays 1000 am 600 pm Satur day Sunday Admission free Stan suggests picture taking have plenty film GOOD flash unit light ing best old seetion muse um excellent new section Also plan make visit two days almost im possible see sections anything less might also note bus service 15 minutes main displays restoration section open adults museum houses airplane flono flyer ROCKET PLANE xP-1 / Only $395 CaIts FunI plus $1/orderGoes up like rocket Ste HGlides down like plane Au Baisa/Ready FiylAttractiveiy Packaged WANTED Distributors ers Increase Profits e Details Jim Masseys Quality Model Products Valley View Dr Box 43 ni 61 37264OBAiiegany NY 14706 March 1989 173 IL@CTITE Teekiqude WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries chargers need packagel Cycler-Charger*19995GO4Wet Cell & Fits 48V Rx 96V Tx packsPlus $5 S&H.ceGelled Cell Others available write call Trickier $2495 CX 4Z% Regular Model$3995 ForPlus $2 S&HFor field kit small Plus $2 S&H Multiple AOelectric boat batteriesSpecify 6 12 24V Radios Heavy Duty Model.$4995 LO sport winch large boat andPlus $250 S&H electric power charging batteriesSpecify 6 1 2V ProductsSASEtorinlormationPO Box 221 CaRa Dealer Inqulnes unitedCanton SD 57013 BOB HOLMAN HAS MORE THAN JUST PLANS Models built plans have won Toledo Best Show World Scale Meet Masters Can other service make claim plans British Magazine also have Most Scale Send $900 two British Plans Books Best Scale catalog F4U-1 EPOXY SMI KIT 75 SPAN TBF-C1 AVENGER EPOXY SMI KIT 82 SPAN Plan Fuselage cowl canopies Best Show Toledo $16195 pp FB VI MOSQUITO 82 SPAN Plan Nacels canopy Spinners Fuselage $19995 p p Plan Fuselage Cowl canopy Ribs Spinner SPITFIRE MKI EPOXY SMI KIT 72 SPAN $17195 pp Plan Fuselage Cowl Canopy Ribs Balsa F6F HELLCAT EPOXY KIT 64 SPAN $19195 pp PLANS Spitfire lA69 Mosquito Fee71 Kit tyhawk 1 A65 P47Thunderbolt . 61 Tempest561 BT-13 Valiant 73 F4U-1 Corsair 61 Harvard .. P-SlBandO61 Fw19OA-460 Btl9Oe61 BtllOc71 F6F-6 Hellcat64 Kawanishi George 64 Spitfire 14 & 19 . 69 OS2U Kingfisher . 56 Gladiator56 Hurricane I70 PLANS $25 EACH OR SHIPPING THE BEST IN SCALE Bob Holman PO Box 741-MA San Bernardino CA 92402 planning build Scale project visit might worthwhile obtain pictures take notes pocket tape recorder handy see firsthand details might incorporate model information call write US Air Force Museum Wright-Patterson AFB OH 45433-6518 Phone 513 255-3284 Documentation source note LF Jim Pepino president Scale Plans Photo Service says new 66-page catalog now available includes photo packs plans three-views Jim provides plan en largement reduction service Photo paeks depending size contain front side rear views plane well close-ups some finer details need landing gear flaps surfaces controls cock pit instrumentation Plan enlarging done using blueprint process Plans available major categories Scale modeling includ ing Control Line course listed RC could candidates conver sion CL wish catalog send $4 SPPS 3209 Madison Ave Greensboro NC 27403 CL Combat/Johnson Continued page 64 Wasp require little work Does kits include just about everything need ex cept adhesive sample kits sent balsa very nicely cut en gine mount assembly put together semi finished model features Voodoo-style leading edge has full-depth spar solid trailing edge just over 400 sq area Profes sional Combat fliers will likely have own fa vorite model wont bother offering slightly less serious Judging lot experience similar models would expect perform well enough place contests does give away foam kill advantage because its solid-wood wing leading edge Oh well get tired patching string cuts foam anyway Does Generix kits calls seem like really good values dollar could fin ished evening recommended super glue Doe holed up palatial estate Ja sonville during winter now would good time get touch him Does Gener tx PO Box Ill Jasonville IN 47438 Prices less $20 Combat kits has sport Stunt kits too What better power new model Nelson 15 examples now come configurations before more-orless standard model rear intake/rear ex haust AAC aluminum/aluminum/chrome piston cylinder constructionRMcM seen domestic foreign FAI Combat models variation engine side-exhaust rear intake original version wtth front intake side exhaust version probably FAI Combat rear intake/rear exhaust model wtth short front end Henry likes confuse other options such ABC liner/piston rather AAC titanium crankshafts just glowengine selection Dont ask about die sels Call Henry Nelson 412 538-5282 infor mation about line sophisticated engines Prices start $175 standard Combat en gine isnt cheapbut theyre best can buy After years battling other en gines Im taking easy way out using Nelson rear intake/rear exhaust AAC setup short nose help cut down weight shorten nose moment models still may win anythingbut Ill look spectac ular losing currently trend Combat model de sign toward rear-set engine prop some close leading edge wing cant get hand hold launch lightweight carbon tail boom has made possible shove engine way back wing such short nose moment model requires long tail moment keep wobbling across sky conventional wood tail booms too heavy made long enough stiff enough resist flying loads result frequently tail-heavy model much fun fly havent seen such model yet just pic ture conventional model boom Drill hole through trailing edge en gine mount Shove carbon fiber arrow shaft some epoxy mount tail feath ers Most modern designs also have controls mounted arrow shaft too small piece aluminum loops around shaft bellcrank bolted seems plenty strong Fast Combat models makes practically indestructible center section also another trend thats away external fuel bladderwhich proba bly good idea Weve found regular Fast Combat bladders work really well skinny tubes models tubing never expands size allowed 1 25-in-diameter tubes use FAI needle setting much better using tubing weve yet break Another plus dont have have special bladders model Cartiers group seems having good luck using open fuel pods models tubing allowed expand whatever size wants claims better performance using style conventional tubing compart ment Greg Hill used two compartments side engine mount equalize dis tribution weight suppose ultimate config uration would having tube front CG behind masses centered middle model know lot guys use outboardlocated fuel ballast lieu adding wing tip weight fuel burns off results plane getting looser lines makes landing thrill Doctor Design claims about nine grams wing tip weight required 48-in-span model offset tendency lines kick outside tip forward plane coming out turn Too much weight sure makes wing cock back turns maybe hes Onto something Wed eyeing Taipan 8 x 6 prop use Fast Combat models hub looked little small performance prop Fox better 8 x 6 wed using threw blade off buzzed up Hoffelt 36R Upon close inspection found air bub bles hub area made up about 30% area gulp failure Tai pan Ive encountered mainly because spun up way above its design limit de sign seems great wed better wait until its available carbon glass Continued page 176 174 Model Aviation
Edition: Model Aviation - 1989/03
Page Numbers: 62, 168, 169, 173, 174
I THOUGHT wed spend time together month talking about couple engine problems received letter few months back Charly Pate Nashville TN Along few nice words about column Nats Charly askd following question What determines fuel tank should placed fuel tank heights referred relationship needle valve ie Set cen ter fuel tank needle valve etc Often tanks location shown plans remember Al Rabe once made fixture allowed him raise lower needle valve hoping coure fine tune engine shimming tank fail ure Sure would like see some comments Youre absolutely right Charly years standard recommendation has line up centerline tank needle valve ever Al others have found doesnt always trick Thus shimming position either tank engine obtain equal engine speeds plane either upright inverted has become necessary nui sance Stunt fliers ception know Fox 35 mounted either upright inverted one-inch-high tank mounted same level will almost always run exactly same both ways seemed clue somewhere put thinking cap re tired personal pondering place Fox 35 hand ST 46 other After consuming substantial sheets paper am ple ration caffeine heres what came up know little two-cycle wonders produce prodigious horsepower might aware secondary function performed engines bottom end ie crankcase area below piston part engine functions very efficient displacement pump performs two tasks First bottom stroke BDC bot tom dead center piston compresses charge fuel air crankcase cylinder bypass/intake ports open charge forced combustion chamber next compression/power-stroke sequence Second top compression stroke TDC top dead center volume beneath piston has enlarged because area sealed increased volume reduces pressure air trapped therein intake port crankshaft opens negative pressure neg ative respect surrounding atmospheric pressure draws air rapidly through venturi past spray bar thereby drawing fuel tank crankcase along Th IS LATED NIDIIAS EIIFIN III SCM NP FIOURE IIIEIKAIRtUIIC 7N CPA.. WNRIC IETERRIRAIIE IF TIE CIffiER IF N1193 ETILTI flow incoming air pumping action al ternately increasing decreasing pressure within crankcase coupled appropriate opening closing exhaust intake ports draws fuel tank rate fuel delivered engine thus determined relationship fuel tank pump trick deter point pump will call Center Pumping Action CPA Continued page 168 Ted just show off graphics capability new toy. er. computer believes hes solved longstanding mystery Stunt technology know position fuel tank engine will run same speed model either upright inverted Hes generated convincing answer months column Figure IV shows intake exhaust ports atypical 2-cycle engine positioned cylinder liner now somebody takes engine apart reassembles cylinder sleeve backwards occurs kind troublesome things happen engine performance including tremendous loss power 62 Model Aviation Conoi Line Aerobatics Ted Fancher 158 Flying Cloud Isle Foster ClAy CA 94404 Gerald Schamp Albany OR built hybrid imltationlOrlental Stunter really beautiful redand-white model Power originally OS 4OFP inadequate planes weight Additional power now comes Tom Lay-tuned ST 60 Closeup Below R shows double horn/double davis arrangement used round adjustment rudder offset RENIH PRESSURE RD EliOt lEE CENTER P119 IEDIT ~1~ ATEC -AIJIIICATER PIN VILE AT MITE OEM CENTER FIGURE IINISIPIESSIREAT IIETE-CVCIIEIIOIE IIF~iI TC9CEMCENTER jAPJ iiiEF Pill IIEIINIT in2Wh AT TIC Ij ATES FliP fLUE ST TEl OEM CENTER Tom Lay T&L Specialties says custombuilt ST 60s produce much power broke arm just starting up Hell still sell you order direct PO Box 6052 Torrance CA 90504 RELATIVE LOCATIONS OF INTAKE AND EXHAUST PORTS EXHAUST PORTS INTAKE1131 WES YIRST 58 PORTSP151W SOCKIWI CWKH eAST FXt3LIEE IJ Tie tiew dot Electarseic Ss*sJhaearLlghfest Weight Rdy4-Mmt EaghsI New Prop adapter Byrons 4 3 bleded1 props AlE CiupbtFIts Sedi ermglnewItt 718 boh pattern NeEhbg EXfr5 pius shipping 27 00 NOCOT0 Law 200MM tammly RotteN$24995 ness body wheel pants cowl Ship fr Hsnd *43000 Foam wing balsa Included *48000 @phiemaMEeg*ees New 2-piece wieg ewiesIoai 5 Thmupied 34 bIOeZ0zUHIJI 407Dl5 nres OaI Customized front newest Garmsn engines puts Muffler Mount Moemtkig Baits Ptssaure Tsp Smoke ________________________ Carburetor Linksge COI Ignition CII Electroniosi 48 Volt Ignition Peck Safety Swisit SIsflolt Hub Resistor Spark Plugs Year Warrenty Faulty Parts Workmeneh T G MFGU 857 HIgh Moutal Rd North Haled. NJ 07508 274845 Made USA Curtiss Jenny * Quality hand-cut kit complete plans rigging scale control setup wire parts pro-bent custom hardware included parts individually identified packaged Complete decals * Engine sizes 26 50 FS 25 TS * Wing unit removes four screws less 3 minutes flying wires left intact * Superb flight characteristics 15900 VISA e MasterCard Money Order Michigan residents add 4% asiec tax Add *550 P81 US orders $1500 foreign Video Catalog 81500 poet rid VHSIBeta Regular Catalog choice Mini-Plan Hand-Cut Quality Affordable Price AERODROME MODELS LTD j1 Saginaw MI 48603 __517 781-3000 Other Kits Available Aero-Pacer Baby -Pacer Gipey Moth Flybaby Flybaby Combo Hawker Hurricane Jester deny pointed out same drawing published Flygning 1950 officers checked found correct quickly ended investiga tion prototype SAAB Dra ken delta jet unveiled long after wards Karlstrom shown proph et has great deal Bjorn Karlstrom aviation illustration creating space comics impressive achievements very active modeler during 1930s 1940s spe cializing large Scale models such Stin sons Fairchilds 1944 produced FLYG 44 first diesel-engined Free Flight craft Scandinavia exhibit really good flying characteristics Long before 1938 built simple rubberpowered Free Right model used mechanism resembling wide-chord pivot ing wing struts roll control Toward end active building career Karlstrom became popular speak er giving lectures numerous model clubs building small Scale airplanes continues create cutout paper models have appeared About Hobby magazine form inserts Such multifaceted involvement avia tion would have exhausted people Bjom Karlstrom found time yet another role industrial designer drafts man During 1950s 1960s created variety successful vehicle designs also illustrated trucks Scania-Vabis locomotives Motala Verkstad 1952 1965 designed mopeds built Crescent firm pop ular 2000 moped likened critic sculpture designed boats pow ered outboard motors including Pi dinghy 1600 sold Swedish magazine Motor published plans two motorboats Ballerina 50-hp Mercury engine could hit 45 knots nifty little SAAB Sonnett TI sports car body designed Karlstrom went far afield design home freezer streamlined lawn mower Karlstrom achieved formal engineering training gifted eye design methodical mind made up lack lifetime creativ ity has brought rewards 6ther finan cial Karlstrom presented Sod erberg Plaque Swedish Aviation tory Association 1981 received treasured Paul Tissandier Diploma Federation Aeronautique Internationale FAJ next time look set scale drawings notice familiar name bracing Scandinavian ring take mo ment think about man behind pen Now know range depth contribution aviation aeronautical design seeing Bjorn Karlstroms name will conjure up images ice-bound fjords snowshoes glittering craggy peaks Without ever setting foot west ern side Atlantic talented knowledgeable man has great impact people American aviation CL Aerobatics/Fancher Continued page 62 physical point engine/pump senses fuel mass neither above nor below position fuel pickup tube inside tank point end uniflow tube case uniflow tank engine/pump will dis cern no difference between upright inverted flight engine rpm will remain same Given premise made some assumptions developed some theories disassem bled measured both Fox 35 ST 46 engines am familiar verify conclusions first assumed bottom crankcase lower fixed end pump top inside piston upper variable end also assumed volume pump consistent throughout isnt course since upper end composed both uni formly round walls cylinder plus pass area bottom end irregularly shaped lower crankcase bore intake passage crankshaft theorized center pump top bottom would approximate ear defined Center Pumping Action Thi theory complicated fact pum TDC has significantly greater volume BDC theoretical solution dilemm assume CPA would located point midway between average heights thi 168 Model Aviation pump TDC BDC verify theory disassembled Fox measured accurately possible Pump height BDC measured bottom crankshaft web location crankpin top inside piston Pump height TDC calculated adding length piston stroke height BDC Since engine mounts located cen terline crankshaft calculated onehalf diameter backplate opening below engine mount thus dimension subtracted calculated CPA would equal proper height tank fuel pickup uniflow tube location above engine mounts numbers Fox 35 Displacement0352 cu Bore0800 Stroke0700 Diameter backplate open inglOS Pump dimensions Pump depth BDC1 700 Pump depth TDC2400 Average pump depth2050 Calculations Midpoint average pump depth CPA1025 Subtract half backplate openingminus 0525 Height CPA above engine mounts0500 rise surprise Remember just few para graphs back mentioned one-inch-thick Stunt tank mounted same level Fox 35s engine mounts just about guaranteed run equally well both upright inverted Well fuel pickup tube Stunt tank exactly half way up tank golly half inch injust like calculated impressed did same thing ST 46 equivalent set numbers Displacement046 cu Bore0865 Stroke0782 Diameter backplate opening1100 Pump dimensions Pump depth BDC1 787 Pump depth TDC2569 Average pump depth2 180 Calculations Midpoint average pump depthi 090 Subtract half backplate opening0550 Height CPA0540 ST calculations indicate need either thicker tank shimmed off mounts match calculated CPA agrees closely personal experience ST Its interesting note needle valve height ST over 0800 off mount normal inverted-engine installation tank mounted line needle valve engine would run rich inverted lean upright feel conclusions sound could safely used starting place locating tank Unfortunately previously mentioned varia bles volume top bottom ends crankcase make such solution still approxi mate Provision should still made final shimming fine tune run addition CPA very clumsy deter inasmuch requires taking engine apart measuring some dimensions go ing approximate best expecting make precise calculations based ap proximations has simpler way ink Based limited sampling suggest Continued page 173 Youll notice power bargain fuels * Special Detergents Promote clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed FREE SHIPPING ON ORDERS OVER $1500 SIG CHAMPION 2-STROKE FUEL PINT QUART GALLON 0% Nitromethane$1075 5% Nitromethane$365 $525$1275 10% Nitromethane$415 $550$1475 15% Nitromethane$430 $635$1675 25% Nitromethane$515 $795$2195 35% Nitromethane$595 $925$2695 SIGPREMIUM 4-STROKEFUEL 10% Nitromethane$1425 15% Nitromethane$1625 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 995% pure very best grade money can buy also use real 100% pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels con tain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price March 1989 169 Revised Lightweight Dual Spoiler ModuleAT4043 duel spoilers made rigid pvc weigh 3 oz per set closed position total overali height 181 Yi inches modifiable 1 inch unmodified blades fufly extended total overall height h 2% inches modules accuate extremely smooth easily single module 5116 inches thick bv6 inches long Modules can ganged end-to-and longer increased surface area Only *1436 per set Ask local hobby shop today Dealers ask ACE RIC Inc detailsI AL-TEC PRODUCTS INC 18800 St Rt 47E ey OH 45365 513 498-1721 CL Aerobatics/Fancher Continued page 168 align fuel pickup tube uniflow vent top backplate opening starting place case Fox ST old OS Max 35 Stunt calculations actual measurements practical examples worked out within few hundredths inch Since layout almost two-cycle Stunt en gines quite similar should very little variation between engines Users four-cycle engines should determine CPA engines based volume combustion chamber TDC BDC since top end engines produces pumping action hope proves helpful tell body heard Urtnowski Just kidding Windy Please dont send alligators after New subject ST 46 took apart measure foregoing bit belongs young friend Paul Pomposo extremely excited about learning Stunt bought used someone installed new Imitation arrived field couple weeks back Paul already practically worn Out trying start ST Well aint never seen 46 wouldnt run asked him let give try After hour work finally got thing run ning sounded like anemic 049 try ing swing 10 x 6 Top Flite No guts Plus af ter quitting midflight engine extremely hot including lower crankcase Ordinarily bottom end two-cycle en gine should run very cool because expand ing fuel/air mixture constantly runs through Although crankshaft bearing seemed little tight rough didnt seem bad enough cause excessive heat surely something wrong suggested Paul remove engine put toolbox could look later Sure enough upon disassembly problem came obvious previous owner installed cylinder liner turned 1800 its correct po sition exhaust ports aligned take bypass crankcase intake ports aligned exhaust Take look Figure IV depicts gener ic cylinder liner Youll note exhaust ports located higher cylinder wall intake ports very good reason two-cycle engine after combustion takes place piston driven downward until LHC-06 CLEAR SILICONE Ideal areas high vibration Waterproofs insulates Stays soft flexible Use glue seal tanopys wing saddles other areas. SEAL BOAT WATERPROOFPUSHRODS AND RADIO BOXESFITTINGS ATTACH FUEL TANKS TO HULLS AND FUSELAGES Available quality hobby shops everywhere Loctite isa registered trademark Loctite Corporation two things happen very rapid succession First burnt gases expelled second fresh charge fuel/air mixture forced com bustion chamber upcoming compression stroke reason exhaust port opens first high-pressure exhaust gases can expel selves establish flow path out exhaust stack split second later full scavenging exhaust gases completed flow fresh charge chamber charge impacts piston baffle circulates up com bustion chamber back down toward ex haust flushing almost spent charge process case Pauls engine liner installed backwards intake ports will open first thereby allowing high-pressure combus tion gases forced incoming charge both dilutes charge burnt gases heats up bottom end engine result very hot-running engine produces little power extremely hard start fact may run isnt rare might think Pauls fourth example Ive seen modeling career youve got used engine exhibits characteristics check Out Look exhaust port can see intake ports far side obviously higher exhaust ports liner backwards Take apart fix CL Scale/Boss Continued page 63 several suggestions would make visit enjoyable especially anyone going first time museums displays quite impressive over 175 aircraft starts beginning flight first aircraft continues worlds sophisticated aircraft B lA bomber new Modem Flight Gallery cludes some following B-52D AT9 Lock heed YF-12A F4C Phantom II C-47D XB-70 B-58 Hustler PRY Catalina NA X-15A B-26 others Visiting hours 900 am 500 pm weekdays 1000 am 600 pm Satur day Sunday Admission free Stan suggests picture taking have plenty film GOOD flash unit light ing best old seetion muse um excellent new section Also plan make visit two days almost im possible see sections anything less might also note bus service 15 minutes main displays restoration section open adults museum houses airplane flono flyer ROCKET PLANE xP-1 / Only $395 CaIts FunI plus $1/orderGoes up like rocket Ste HGlides down like plane Au Baisa/Ready FiylAttractiveiy Packaged WANTED Distributors ers Increase Profits e Details Jim Masseys Quality Model Products Valley View Dr Box 43 ni 61 37264OBAiiegany NY 14706 March 1989 173 IL@CTITE Teekiqude WHEN YOU FORGET\OUR UNITS REMEMBER RC System NICd Batteries chargers need packagel Cycler-Charger*19995GO4Wet Cell & Fits 48V Rx 96V Tx packsPlus $5 S&H.ceGelled Cell Others available write call Trickier $2495 CX 4Z% Regular Model$3995 ForPlus $2 S&HFor field kit small Plus $2 S&H Multiple AOelectric boat batteriesSpecify 6 12 24V Radios Heavy Duty Model.$4995 LO sport winch large boat andPlus $250 S&H electric power charging batteriesSpecify 6 1 2V ProductsSASEtorinlormationPO Box 221 CaRa Dealer Inqulnes unitedCanton SD 57013 BOB HOLMAN HAS MORE THAN JUST PLANS Models built plans have won Toledo Best Show World Scale Meet Masters Can other service make claim plans British Magazine also have Most Scale Send $900 two British Plans Books Best Scale catalog F4U-1 EPOXY SMI KIT 75 SPAN TBF-C1 AVENGER EPOXY SMI KIT 82 SPAN Plan Fuselage cowl canopies Best Show Toledo $16195 pp FB VI MOSQUITO 82 SPAN Plan Nacels canopy Spinners Fuselage $19995 p p Plan Fuselage Cowl canopy Ribs Spinner SPITFIRE MKI EPOXY SMI KIT 72 SPAN $17195 pp Plan Fuselage Cowl Canopy Ribs Balsa F6F HELLCAT EPOXY KIT 64 SPAN $19195 pp PLANS Spitfire lA69 Mosquito Fee71 Kit tyhawk 1 A65 P47Thunderbolt . 61 Tempest561 BT-13 Valiant 73 F4U-1 Corsair 61 Harvard .. P-SlBandO61 Fw19OA-460 Btl9Oe61 BtllOc71 F6F-6 Hellcat64 Kawanishi George 64 Spitfire 14 & 19 . 69 OS2U Kingfisher . 56 Gladiator56 Hurricane I70 PLANS $25 EACH OR SHIPPING THE BEST IN SCALE Bob Holman PO Box 741-MA San Bernardino CA 92402 planning build Scale project visit might worthwhile obtain pictures take notes pocket tape recorder handy see firsthand details might incorporate model information call write US Air Force Museum Wright-Patterson AFB OH 45433-6518 Phone 513 255-3284 Documentation source note LF Jim Pepino president Scale Plans Photo Service says new 66-page catalog now available includes photo packs plans three-views Jim provides plan en largement reduction service Photo paeks depending size contain front side rear views plane well close-ups some finer details need landing gear flaps surfaces controls cock pit instrumentation Plan enlarging done using blueprint process Plans available major categories Scale modeling includ ing Control Line course listed RC could candidates conver sion CL wish catalog send $4 SPPS 3209 Madison Ave Greensboro NC 27403 CL Combat/Johnson Continued page 64 Wasp require little work Does kits include just about everything need ex cept adhesive sample kits sent balsa very nicely cut en gine mount assembly put together semi finished model features Voodoo-style leading edge has full-depth spar solid trailing edge just over 400 sq area Profes sional Combat fliers will likely have own fa vorite model wont bother offering slightly less serious Judging lot experience similar models would expect perform well enough place contests does give away foam kill advantage because its solid-wood wing leading edge Oh well get tired patching string cuts foam anyway Does Generix kits calls seem like really good values dollar could fin ished evening recommended super glue Doe holed up palatial estate Ja sonville during winter now would good time get touch him Does Gener tx PO Box Ill Jasonville IN 47438 Prices less $20 Combat kits has sport Stunt kits too What better power new model Nelson 15 examples now come configurations before more-orless standard model rear intake/rear ex haust AAC aluminum/aluminum/chrome piston cylinder constructionRMcM seen domestic foreign FAI Combat models variation engine side-exhaust rear intake original version wtth front intake side exhaust version probably FAI Combat rear intake/rear exhaust model wtth short front end Henry likes confuse other options such ABC liner/piston rather AAC titanium crankshafts just glowengine selection Dont ask about die sels Call Henry Nelson 412 538-5282 infor mation about line sophisticated engines Prices start $175 standard Combat en gine isnt cheapbut theyre best can buy After years battling other en gines Im taking easy way out using Nelson rear intake/rear exhaust AAC setup short nose help cut down weight shorten nose moment models still may win anythingbut Ill look spectac ular losing currently trend Combat model de sign toward rear-set engine prop some close leading edge wing cant get hand hold launch lightweight carbon tail boom has made possible shove engine way back wing such short nose moment model requires long tail moment keep wobbling across sky conventional wood tail booms too heavy made long enough stiff enough resist flying loads result frequently tail-heavy model much fun fly havent seen such model yet just pic ture conventional model boom Drill hole through trailing edge en gine mount Shove carbon fiber arrow shaft some epoxy mount tail feath ers Most modern designs also have controls mounted arrow shaft too small piece aluminum loops around shaft bellcrank bolted seems plenty strong Fast Combat models makes practically indestructible center section also another trend thats away external fuel bladderwhich proba bly good idea Weve found regular Fast Combat bladders work really well skinny tubes models tubing never expands size allowed 1 25-in-diameter tubes use FAI needle setting much better using tubing weve yet break Another plus dont have have special bladders model Cartiers group seems having good luck using open fuel pods models tubing allowed expand whatever size wants claims better performance using style conventional tubing compart ment Greg Hill used two compartments side engine mount equalize dis tribution weight suppose ultimate config uration would having tube front CG behind masses centered middle model know lot guys use outboardlocated fuel ballast lieu adding wing tip weight fuel burns off results plane getting looser lines makes landing thrill Doctor Design claims about nine grams wing tip weight required 48-in-span model offset tendency lines kick outside tip forward plane coming out turn Too much weight sure makes wing cock back turns maybe hes Onto something Wed eyeing Taipan 8 x 6 prop use Fast Combat models hub looked little small performance prop Fox better 8 x 6 wed using threw blade off buzzed up Hoffelt 36R Upon close inspection found air bub bles hub area made up about 30% area gulp failure Tai pan Ive encountered mainly because spun up way above its design limit de sign seems great wed better wait until its available carbon glass Continued page 176 174 Model Aviation